Vapor Compression Cycle Utilizing Ionic Liquid as Compressor Lubricant

ABSTRACT

This invention relates to the use of ionic liquids as lubricants in vapor compression systems for cooling or heating. This invention also relates to an apparatus for adjusting temperature that operates a vapor compression cycle.

This application claims the benefit of U.S. Provisional Application No.60/809,622, filed May 31, 2006, which is incorporated in its entirety asa part hereof for all purposes.

TECHNICAL FIELD

This invention relates to the operation or execution of a vaporcompression cycle using a compressor, wherein at least one ionic liquidis provided as a lubricant for the compressor.

BACKGROUND

Many refrigeration, heating and air-cooling and air-heating systemsoperate using a vapor compression cycle. This cycle consists ofcompressing refrigerant gas from a low pressure to a high pressure. Thehigh-pressure gas exits a device used for increasing the pressure of therefrigerant, typically a compressor, and is condensed to a liquid,typically by a heat exchanger called a condenser, where heat is removedfrom the refrigerant. The high-pressure liquid refrigerant is lowered inpressure through an expansion device (valve or capillary tube) and therefrigerant liquid expands to a gas through a second heat exchangercalled an evaporator where heat is absorbed by the refrigerant. Thisprocess of removing and absorbing heat produces a heating and coolingaffect, which can be used for refrigeration, air-conditioning, andheating.

While all of these steps are important, the compression step is acrucial part of the cycle (Fluorocarbon Refrigerants Handbook, R. C.Downing, Prentice-Hall, Inc. 1988). When a compressor is used tomechanically increase the pressure of a refrigerant, a lubricant (i.e.oil) is needed in the compressor to lubricate the compressor bearingsand other moving parts, and the properties of the oil must be suitablefor this purpose. Often the oil leaves the compressor by slipping (i.e.leaking) past the piston rings in reciprocating compressors, byentrainment with the refrigerant, and by excessive foaming asrefrigerant is released from solution in the oil. A small amount of oilcirculating with the refrigerant may not cause any significant problems;however, if the oil accumulates in the system over time, the oil levelin the compressor can become critically low and the compressor bearingsand other moving parts can overheat and fail. Many sealed (hermetic)compressors are used for refrigerators, window air-conditioners,residential heat pumps, and commercial air-handlers. These compressorsare precharged at the factory with the correct amount of oil, and a dropin oil level can reduce the life expectancy for these machines.

Problems related to compressor oil migration in a vapor compressionsystem are related to the fact that oil may accumulate in the evaporatorand cause a decrease in the cooling capacity of the system. Designers ofrefrigeration and air-conditioning systems often install oil separatorsin the discharge line of the compressor to trap oil and return it to thecompressor crankcase. The oil is pushed along in the condenser by theliquid refrigerant and in the evaporator and suction line back to thecompressor by the velocity of the refrigerant gas. The refrigerant pipescan also be designed to allow the oil to flow downhill back to thecompressor using gravity. When oil leaves the compressor, however, itmay or may not be soluble in the refrigerant, and the more soluble therefrigerant is in the oil, the better oil return to the compressor willbe. The refrigerant dissolves in the oil, and reduces the viscosity ofthe oil that assists with the oil moving through the piping back to thecompressor. Although these measures can be helpful, they are not 100%effective and may postpone the problem rather than solve it completely.For example, when there is a drop in the cooling capacity of the system,high temperatures in the compressor can lead to thermal breakdown andcopper plating on valve surfaces, thus interfering with the properoperation of the compressor. Sludging and acid formation may limit thelife of the system.

Several classes of commercial oils exist. Historically, the most commonlubricants were natural or mineral-based oils (MO). Initially, when mostrefrigerants were based on chlorofluorocarbons (CFCs), the chlorinecontent in the refrigerant [i.e. fluorotrichloromethane (CFC-11) anddifluorodichloromethane (CFC-12)] provided excellent solubility withmineral oil. With the development of the hydrofluorocarbon (HFC)refrigerants to replace CFCs, mineral oil had little to no solubilitywith the new refrigerants [e.g. 1,1,1,2-tetrafluoroethane (HFC-134a)].Therefore, new synthetic based lubricants such as polyalkeneglycol-based oil (PAG) and polyolester-based oil (PO) were developed.Although the new synthetic oils had better solubility with the HFCrefrigerants, the solubility was still not as good as that of CFCs andmineral-based oils. Furthermore the PAG and PO oils are not as effectiveas lubricants, and additive packages must be mixed with the syntheticoils to improve their lubricating performance. Refrigerant gases otherthan HFCs, such as non-fluorinated hydrocarbons and carbon dioxide(CO₂), have been proposed. Non-fluorinated hydrocarbons have excellentsolubility in MOs, however no suitable lubricant has been found for CO₂refrigeration and air-conditioning compressors.

Ionic liquids have been described as potential lubricants. Wang et al[WEAR (2004) 256:44-48] and Ye et al [Chem. Comm. (2001) 21:2244-2245]describe the tribological properties and predicted lubricantfunctionality of alkylimidazolium hexafluorophosphate andalkylimidazolium tetrafluoroborate, respectively. WO 05/35702 disclosesthe heat resistance and friction characteristics of lubricating oilscontaining ionic liquids as base oils.

A need nevertheless remains for lubricants that are well suited for usein conjunction with the current and new refrigerants that are used in avapor compression system. A lubricant with high solubilty for HFCs andCO₂, for example, would be desirable to replace, or be mixed with,traditional synthetic oils such as PAGs and POs to increase theoperating lifetime of vapor compression systems. As a result, ionicliquids are disclosed herein, for use with various refrigerants in avapor compression system, as type of compressor lubricant having abalance of properties that is superior to that of the current syntheticlubricants.

SUMMARY

The present invention relates to the use of ionic liquids as lubricantsin the compressor of a vapor compression system that provides cooling orheating.

In one embodiment, this invention provides an apparatus for temperatureadjustment that includes

(a) a compressor that increases the pressure of the vapor of at leastone refrigerant, wherein the compressor comprises moving parts that arelubricated by at least one ionic liquid;

(b) a condenser that receives refrigerant vapor that is passed out ofthe compressor, and condenses the vapor under pressure to a liquid;

(c) a pressure reduction device that receives liquid refrigerant that ispassed out of the condenser, and reduces the pressure of the liquid toform a mixture of refrigerant in liquid and vapor form;

(d) an evaporator that receives the mixture of liquid and vaporrefrigerant that is passed out of the pressure reduction device, andevaporates the remaining liquid in the mixture to form refrigerantvapor; and

(e) a conduit that returns to the compressor refrigerant vapor that ispassed out of the evaporator.

In another embodiment, this invention provides an apparatus fortemperature adjustment that includes

(a) a compressor that increases the pressure of the vapor of at leastone refrigerant;

(b) a condenser that receives refrigerant vapor that is passed out ofthe compressor, and condenses the vapor under pressure to a liquid;

(c) a pressure reduction device that receives liquid refrigerant that ispassed out of the condenser, and reduces the pressure of the liquid toform a mixture of refrigerant in liquid and vapor form;

(d) an evaporator that receives the mixture of liquid and vaporrefrigerant that is passed out of the pressure reduction device, andevaporates the remaining liquid in the mixture to form refrigerantvapor; and

(e) a conduit that returns to the compressor refrigerant vapor that ispassed out of the evaporator;

wherein a refrigerant is admixed with at least one ionic liquid.

Either of these apparatus may adjust temperature by absorbing heat from,or transferring heat to, an object, medium or space. In such anapparatus, the condenser may for example, be located in proximity to anobject, medium or space to be heated; or the evaporator may be locatedin proximity to an object, medium or space to be cooled.

In a further embodiment, this invention provides a process for adjustingthe temperature of an object, medium or a space by

(a) providing a mechanical device having moving parts to increase thepressure of the vapor of at least one refrigerant, and providing atleast one ionic liquid to lubricate the moving parts of the device;

(b) condensing the refrigerant vapor under pressure to a liquid;

(c) reducing the pressure of the liquid refrigerant to form a mixture ofrefrigerant in liquid and vapor form;

(d) evaporating the liquid refrigerant to form refrigerant vapor; and

(e) repeating step (a) to increase the pressure of the refrigerant vaporformed in steps (c) and (d).

In yet another embodiment, this invention provides a process foradjusting the temperature of an object, medium or a space by

(a) increasing the pressure of the vapor of at least one refrigerant;

(b) condensing the refrigerant vapor under pressure to a liquid;

(c) reducing the pressure of the liquid refrigerant to form a mixture ofrefrigerant in liquid and vapor form;

(d) evaporating the liquid refrigerant to form refrigerant vapor;

(e) separating from the refrigerant vapor any ionic liquid presenttherein; and

(f) repeating step (a) to increase the pressure of the refrigerant vaporformed in steps (c) and (d).

In either of such processes, temperature may be adjusted by absorbingheat from, or transferring heat to, an object, medium or space. In sucha process, the refrigerant vapor may in step (b) be condensed to aliquid in proximity to an object, medium or space to be heated; or theliquid refrigerant may in step (d) be evaporated to form refrigerantvapor in proximity to an object, medium or space to be cooled.

In yet another embodiment, this invention provides a method foroperating a mechanical compressor that has moving parts by providing anionic liquid as the lubricant for the moving parts.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. is a schematic diagram of a simple vapor compression cycle.

FIG. 2. is a schematic diagram of a simple vapor compressor.

FIG. 3 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-32+[bmim][PF₆] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 4 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-125+[bmim][PF₆] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 5 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-134a+[bmim][PF₆] as a function of pressure. Filledcircles (●) represent measured isothermal data at 10° C., filledtriangles (▴) represent measured isothermal data at 25° C., filledsquares (▪) represent measured isothermal data at 50° C., and filleddiamonds (♦) represent measured isothermal data at 75° C. Solid linesrepresent data trends.

FIG. 6 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-143a+[bmim][PF₆] as a function of pressure. Filledcircles (●) represent measured isothermal data at 10° C., filledtriangles (▴) represent measured isothermal data at 25° C., filledsquares (▪) represent measured isothermal data at 50° C., and filleddiamonds (♦) represent measured isothermal data at 75° C. Solid linesrepresent data trends.

FIG. 7 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-152a+[bmim][PF₆] as a function of pressure. Filledcircles (●) represent measured isothermal data at 10° C., filledtriangles (▴) represent measured isothermal data at 25° C., filledsquares (▪) represent measured isothermal data at 50° C., and filleddiamonds (♦) represent measured isothermal data at 75° C. Solid linesrepresent data trends.

FIG. 8 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-32+[bmim][BF₄] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 9 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-23+[bmim][PF₆] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 10 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-23+[emim][PF₆] as a function of pressure. Filled squares(▪) represent measured isothermal data at 60° C., and filled diamonds(♦) represent measured isothermal data at 75° C. Solid lines representdata trends.

FIG. 11 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-32+[dmpim][TMeM] as a function of pressure. Filledcircles (●) represent measured isothermal data at 10° C., filledtriangles (▴) represent measured isothermal data at 25° C., filledsquares (▪) represent measured isothermal data at 50° C., and filleddiamonds (♦) represent measured isothermal data at 75° C. Solid linesrepresent data trends.

FIG. 12 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-32+[emim][BEI] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 13 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-32+[emim][BMeI] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 14 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-32+[pmpy][BMeI] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 15 shows measured isothermal solubility data (in mole fraction) ofthe system HFC-32+[bmpy][BMeI] as a function of pressure. Filled circles(●) represent measured isothermal data at 10° C., filled triangles (▴)represent measured isothermal data at 25° C., filled squares (▪)represent measured isothermal data at 50° C., and filled diamonds (♦)represent measured isothermal data at 75° C. Solid lines represent datatrends.

FIG. 16 shows measured isothermal solubility data at 25° C. of thesystems HFC-32+eight different ionic liquids as a function of pressurefor comparison. Open diamonds (⋄) represent measured isothermal data forHFC-32+1-ethyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide,open circles (◯) represent measured isothermal data forHFC-32+1-propyl-2,3-dimethylimidazoliumtris(trifluoromethylsulfonyl)methide at 25° C., open squares (□)represent measured isothermal data forHFC-32+1-propyl-2,3-dimethylimidazoliumbis(trifluoromethylsulfonyl)imide at 25° C., closed diamonds (♦)represent measured isothermal data forHFC-32+3-methyl-1-propylpyridinium bis(trifluoromethylsulfonyl)imide,open triangles (Δ) represent measured isothermal data forHFC-32+1-butyl-3-methylimidazolium hexafluorophosphate at 25° C., filledcircles (●) represent measured isothermal data forHFC-32+1-butyl-3-methylimidazolium tetrafluoroborate at 25° C., filledsquares (▪) represent measured isothermal data forHFC-32+1,3-dioctylimidazolium iodide at 25° C., and filled triangles (▴)represent measured isothermal data forHFC-32+1-octyl-3-methylimidazolium iodide at 25° C. Solid linesrepresent data trends.

FIG. 17 shows measured isothermal solubility data (in mole fraction) at10° C. of the systems HFC-32, HFC-152a, HFC-134a, HFC-125, andHFC-143a+[bmim][PF₆] in terms of absolute pressure divided by the gassaturation pressure at 10° C. shown by ratio (P/P₀). Open diamonds (⋄)represent measured isothermal data for HFC-32 at 10° C. with P₀=11.069bar, open cross hatch (X) represents measured isothermal data forHFC-152a at 10° C. with P₀=3.7277 bar, filled circles (●) representmeasured isothermal data for HFC-134a at 10° C. with P₀=4.1461 bar, opensquares (□) represent measured isothermal data for HFC-125 at 10° C.with P₀=9.0875 bar, filled circles (●) represent measured isothermaldata for HFC-143a at 10° C. with P₀=8.3628 bar. Solid lines representdata trend and dashed line represents Raoult's Law.

FIG. 18 shows a schematic diagram of the gravimetric microbalance usedfor measuring gas absorption in the ionic liquids. In the diagram j₁,j₂, and j₃ refer to the counter-weight, hook and chain, respectively;i₁, i₂ and i₃ refer to the sample container, wire and chain,respectively, W_(g) refers to the force due to gravity; and B refers tothe force due to buoyancy.

DETAILED DESCRIPTION

In the description of this invention, the following definitionalstructure is provided for certain terminology as employed in variouslocations in the specification:

An “ionic liquid” is an organic salt that is fluid at about 100° C. orbelow, as more particularly described in Science (2003) 302:792-793. A“fluorinated ionic liquid” is an ionic liquid having at least onefluorine on either the cation or the anion. A “fluorinated cation” or“fluorinated anion” is a cation or anion, respectively, comprising atleast one fluorine.

A “halogen” is bromine, iodine, chlorine or fluorine.

A “heteroaryl” is an alkyl group having a heteroatom.

A “heteroatom” is an atom other than carbon in the structure of analkanyl, alkenyl, cyclic or aromatic compound.

A “hydrofluorocarbon” is a compound comprising fluorine, carbon, and atleast one hydrogen atom. A hydrofluorocarbon compound (HFC) includes ahydrochlorofluorocarbon (HCFC), wherein HFC and HCFC are common termsused to define refrigerants [see, for example, Ralph C. Downing,Fluorocarbon Refrigerants Handbook, Prentice-Hall, Inc., EnglewoodCliffs, N.J. (1988)]. Hydrofluorocarbon compounds also include compoundsselected from the group consisting of hydrofluoroethers,hydrofluoroketones, hydrofluoroaromatics and hydrofluoroolefins;representative examples of which include methyl nonafluoroisobutylether, methyl nonafluorobutyl ether, ethyl nonafluoroisobutyl ether,ethyl nonafluorobutyl ether, and3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2-trifluoromethylhexane.Hydrofluorocarbon compounds also include compounds wherein one or moresubstituents is bromine, chlorine or iodine.

“Optionally substituted with at least one member selected from the groupconsisting of”, when referring to an alkane, alkene, alkoxy,fluoroalkoxy, perfluoroalkoxy, fluoroalkyl, perfluoroalkyl, aryl orheteroaryl radical or moiety, means that one or more hydrogens on acarbon chain of the radical or moiety may be independently substitutedwith one or more of the members of a recited group of substituents. Forexample, a substituted —C₂H₅ radical or moiety may, without limitation,be —CF₂CF₃, —CH₂CH₂OH or —CF₂CF₂I where the group or substituentsconsist of F, I and OH.

A “refrigerant” is a fluidic substance such as a fluorocarbon (FC),hydrofluorocarbon (HFC), chlorofluorocarbon (CFC),hydrochlorofluorocarbon (HCFC), or carbon dioxide that may be used as athermal energy transfer vehicle. A refrigerant, when it changes phasefrom liquid to vapor (evaporates), removes heat from the surroundings;and when it changes phase from vapor to liquid (condenses), adds heat tothe surroundings. Although the term refrigerant may typically carry theconnotation of a substance used only for cooling, the term is usedherein in the generic sense of a thermal energy transfer vehicle orsubstance that is applicable for use in a system or apparatus that maybe used for heating or cooling by the absorption or rejection of heat ina selected location. For the present invention, the term “refrigerant”can be used to indicate one fluidic substance as described above, or mayindicate a blend or mixture of two or more such fluidic substances.

A “vacuum” is a pressure less than 1 bar but greater than 10⁻⁴ bar forpractical use in extractive distillation equipment.

The present invention relates to the use of ionic liquids as lubricantsin the operatio of a compressor in a vapor compression system thatprovides cooling or heating. This invention thus also relates to anapparatus for adjusting temperature that operates or executes a vaporcompression cycle. The invention also provides a process for temperatureadjustment, either cooling or heating, utilizing a vapor compressionsystem in which an ionic liquid is used as a lubricant.

Vapor compression cycles for cooling or heating are known in the artfrom sources such as Application Guide for AbsorptionCooling/Refrigeration Using Recovered Heat [Dorgan Cb, et al. (AmericanSociety of Heating, Refrigeration and Air Conditioning Engineers, Inc.,1995, Atlanta, Ga., Chapter 5)]. A schematic diagram for a simple vaporcompression system is shown in FIG. 1. The system is composed ofcondenser and evaporator units with an expansion valve and a vaporcompressor. FIG. 2 provides a schematic for a simple vapor compressor.

In FIG. 1, the pressure of the vapor of one or more refrigerants isincreased mechanically by the operation of a compressor. The compressorhas moving parts that are lubricated by a lubricant. In this invention,one or more ionic liquids serve as the lubricant. The refrigerant havingincreased pressure is passed through a conduit to a condenser where itis condensed to liquid form. The action of condensing the refrigerantgenerates heat, which is transferred or rejected to the surroundings,which may be an object, medium or space to be heated. The condensedrefrigerant in liquid from is passed out of the condenser and isreceived into a pressure reduction device such as an expansion valve,where some of the liquid is converted to refrigerant vapor, creating amixture of refrigerant in liquid and vapor form. From there, the mixtureflows out of the pressure reduction device and is received by anevaporator where the liquid refrigerant is evaporated to vapor form. Asheat is absorbed by, and flows into, the evaporater by virtue of thetransformation of the refrigerant from liquid to vapor form, thesurroundings (such as an object, medium or space) lose heat and arecooled. The refrigerant, now all or essentially all in vapor form, isreturned to the compressor where the same cycle commences again.Operation or execution of a vapor compression cycle in this manner canthus be used for temperature adjustment as, by the absorption orexpulsion heat an object (for example a conduit or a container), amedium (for example a fluid such as air or water) or a space can beheated or cooled as desired.

In one embodiment, therefore, this invention provides an apparatus fortemperature adjustment, to operate or execute a vapor compression cycleas described above, that includes (a) a compressor that increases thepressure of the vapor of at least one refrigerant, wherein thecompressor comprises moving parts that are lubricated by at least oneionic liquid; (b) a condenser that receives refrigerant vapor that ispassed out of the compressor, and condenses the vapor under pressure toa liquid; (c) a pressure reduction device that receives liquidrefrigerant that is passed out of the condenser, and reduces thepressure of the liquid to form a mixture of refrigerant in liquid andvapor form; (d) an evaporator that receives the mixture of liquid andvapor refrigerant that is passed out of the pressure reduction device,and evaporates the remaining liquid in the mixture to form refrigerantvapor; and (e) a conduit that returns to the compressor refrigerantvapor that is passed out of the evaporator.

In another embodiment, this invention provides an apparatus fortemperature adjustment that includes (a) a compressor that increases thepressure of the vapor of at least one refrigerant; (b) a condenser thatreceives refrigerant vapor that is passed out of the compressor, andcondenses the vapor under pressure to a liquid; (c) a pressure reductiondevice that receives liquid refrigerant that is passed out of thecondenser, and reduces the pressure of the liquid to form a mixture ofrefrigerant in liquid and vapor form; (d) an evaporator that receivesthe mixture of liquid and vapor refrigerant that is passed out of thepressure reduction device, and evaporates the remaining liquid in themixture to form refrigerant vapor; and (e) a conduit that returns to thecompressor refrigerant vapor that is passed out of the evaporator;wherein a refrigerant is admixed with at least one ionic liquid. In avapor compression system where an ionic liquid is used as a lubricantfor a mechanical compressor, the refrigerant as is circulated throughthe vapor compression cycle may contain some amount of an ionic liquidlubricant where the lubricant has leaked out of its ordinary locationand into other parts of the system where it is conceptually not intendedto be.

Either of such apparatus may adjust temperature by absorbing heat from,or transferring heat to, an object, medium or space. In such anapparatus, the condenser may for example, be located in proximity to anobject, medium or space to be heated; or the evaporator may be locatedin proximity to an object, medium or space to be cooled.

An apparatus of this invention may be deployed for use in, or fabricatedor operated as, a refrigerator, a freezer, an ice machine, an airconditioner, an industrial cooling system, a heater or heat pump. Eachof these instruments may be situated in a residential, commercial orindustrial setting, or may be incorporated into a mobilized device suchas a car, truck, bus, train, airplane, or other device fortransportation, or may be incorporated into a piece of equipment such asa medical instrument.

In another embodiment, this invention provides a process for adjustingthe temperature of an object, medium or a space by (a) providing amechanical device to increase the pressure of the vapor of at least onerefrigerant where the device has moving parts, and providing at leastone ionic liquid to lubricate the moving parts of the device; (b)condensing the refrigerant vapor under pressure to a liquid; (c)reducing the pressure of the liquid refrigerant to form a mixture ofrefrigerant in liquid and vapor form; (d) evaporating the liquidrefrigerant to form refrigerant vapor; (e) repeating step (a) toincrease the pressure of the refrigerant vapor formed in steps (c) and(d).

In another embodiment, this invention provides a process for adjustingthe temperature of an object, medium or a space by (a) passing the vaporof at least one refrigerant through a compressor that has moving partsto increase the pressure of the refrigerant vapor, and providing atleast one ionic liquid to lubricate the moving parts of the compressor;(b) passing the refrigerant vapor out of the compressor and into acondenser to condense the refrigerant vapor under pressure to a liquid;(c) passing the refrigerant in liquid form out of the condenser to apressure reduction device to reduce the pressure of the liquidrefrigerant to form a mixture of refrigerant in liquid and vapor form;(d) passing the mixture to an evaporator to evaporate the liquidrefrigerant to form refrigerant vapor; (e) passing the refrigerant vaporthroughout a conduit to the compressor to repeat step (a) to increasethe pressure of the refrigerant vapor formed in steps (c) and (d).

In yet another embodiment, this invention provides a process foradjusting the temperature of an object, medium or a space by (a)increasing the pressure of the vapor of at least one refrigerant; (b)condensing the refrigerant vapor under pressure to a liquid; (c)reducing the pressure of the liquid refrigerant to form a mixture ofrefrigerant in liquid and vapor form; (d) evaporating the liquidrefrigerant to form refrigerant vapor; (e) separating from therefrigerant vapor any ionic liquid present therein; and (f) repeatingstep (a) to increase the pressure of the refrigerant vapor formed insteps (c) and (d). In a vapor compression system where an ionic liquidis used as a lubricant for a mechanical compressor, the refrigerant asis circulated through the vapor compression cycle may contain someamount of an ionic liquid lubricant where the lubricant has leaked outof its ordinary location and into other parts of the system where it isconceptually not intended to be. When refrigerant that is thus admixedwith an ionic liquid is returned to the compressor for re-pressurizing,the ambient temperature will be at a level at which the refrigerant willbe in vapor form but an ionic liquid will be in liquid form. The returnconduit may thus be designed to permit the ionic liquid, as a liquid, tobe separated from the refrigerant by being drained out through anopening into the lubricant sump while the refringerant vapor, as avapor, passes alone on into the compressor for re-pressurization.

In any of such processes, temperature may be adjusted by absorbing heatfrom, or transferring heat to, an object, medium or space. In such aprocess, the refrigerant vapor may in step (b) be condensed to a liquidin proximity to an object, medium or space to be heated; or the liquidrefrigerant may in step (d) be evaporated to form refrigerant vapor inproximity to an object, medium or space to be cooled.

In one embodiment of the invention, a refrigerant suitable for use in avapor compression system hereof may be selected from one or more membersof the group consisting of CHClF₂ (R-22), CHF₃ (R-23), CH₂F₂ (R-32),CH₃F (R-41), CHF₂CF₃ (R-125), CH₂FCF₃ (R-134a), CHF₂OCHF₂ (E-134),CH₃CClF₂ (R-142b), CH₃CF₃ (R-143a), CH₃CHF₂ (R-152a), CH₃CH₂F (R-161),CH₃OCH₃ (E170), CF₃CF₂CF₃ (R-218), CF₃CHFCF₃ (R-227ea), CF₃CH₂CF₃(R-236fa), CH₂FCF₂CHF₂ (R-245ca), CHF₂CH₂CF₃ (R-245fa), CH₃CH₂CH₃(R-290), CH₃CH₂CH₂CH₃ (R-600), CH(CH₃)₂CH₃ (R-600a), CH₃CH₂CH₂CH₂CH₃(R-601), (CH₃)₂CHCH₂CH₃ (R-601a), CH₃CH₂OCH₂CH₃ (R-610), NH₃, CO₂, andCH₃CH═CH₂, wherein the common name is given in parentheses following thechemical formula. In another embodiment of the invention, therefrigerant useful for the invention can be a blend selected from thegroup consisting of R-125/R-143a/R-134a (44.0/52.0/4.0) (R-404A),R-32/R-125/R-134a (20.0/40.0/40.0) (R-407A), R-32/R-125/R-134a(10.0/70.0/20.0) (R-407B), R-32/R-125/R-134a (23.0/25.0/52.0) (R-407C),R-32/R-125/R-134a (15.0/15.0/70.0) (R-407D), R-32/R-125/R-134a(25.0/15.0/60.0) (R-407E), R-32/R-125 (50.0/50.0) (R-410A), R-32/R-125(45.0/55) (R-410B), R-218/R-134a/R-600a (9.0/88.0/3.0) (R-413A),R-125/R-134a/R-600 (46.6/50.0/3 0.4) (417A), R-125/R-134a/E170(77.0/19.0/4.0) (R-419A), R-134a/R-142b (88.0/12.0) (R-420A),R-134a/R-142b (80.6/19.4), R-125/R-134a (58.0/42.0) (R-421A),R-125/R-134a (85.0/15.0) (R-421B), R-125/R-134a/R-600a (85.1/11.5/3.4)(R-422A), R-125/R-134a/R-600a (55.0/42.0/3.0) (R-422B),R-125/R-134a/R-600a (82.0/15.0/3.0) (R-422C), R-125/R-134a/R-600a(65.1/31.5/3.4) (R-422D), R-134a/R-227ea (52.5/47.5) (R423A),R-125/R-134a/R-600a/R-600/R-601a (50.5/47.0/0.9/1.0/0.6) (R-424A),R-32/R-134a/R-227ea (18.5/69.5/12.0) (R-425A), R-125/R-134a/R-600/R-601a(5.1/93.0/1.3/0.6) (R-426A), R-32/R-125/R-143a/R-134a(15.0/25.0/10.0/50.0) (R-427A), R-32/R-125/R-143a/R-134a(2.0/41.0/50.0/7.0), R-32/R-125/R-143a/R-134a (10.0/33.0/36.0/21.0),R-125/R-143a/R-290/R-600a (77.5/20.0/0.6/1.9) (R-428A), and R-125/R-143a(50.0/50.0) (R-507A), wherein the weight percent of the individualcomponents relative to the other refrigerant components in the blend andthe common name are given in parentheses following each blend.

In another embodiment of the invention, the refrigerant can be selectedfrom one or more members of the group consisting of R-22, R-32, R-125,R-134a, R-404A, R-410A, R-413A, R-422A, R-422D, R-423A, R-426A, R-427Aand R-507A.

In another embodiment of the invention, a hydrofluorocarbon for use as arefrigerant herein is selected from one or more members of the groupconsisting of trifluoromethane (HFC-23), difluoromethane (HFC-32),pentafluoroethane (HFC-125), 1,1,2,2-tetrafluoroethane (HFC-134),1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1-trifluoroethane (HFC-143a),1,1-difluoroethane (HFC-152a), fluoroethane (HFC-161), R-404A, R-407C,and R-410A.

In another embodiment, a hydrofluorocarbon is selected from one or moremembers of the group consisting of pentafluoroethane (HFC-125),1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoroethane(HFC-134a), R-404A, R-407C, and R-410A.

Mixtures of refrigerants or blends may also be used.

In another embodiment, the refrigerant can be at least one fluoroolefinselected from the group consisting of:

-   -   (i) fluoroolefins of the formula E- or Z-R¹CH═CHR², wherein R¹        and R² are, independently, C₁ to C₆ perfluoroalkyl groups, and        wherein the total number of carbons in the compound is at least        5;    -   (ii) cyclic fluoroolefins of the formula        cyclo-[CX═CY(CZW)_(n)-], wherein X, Y, Z, and W, independently,        are H or F, and n is an integer from 2 to 5; and    -   (iii) fluoroolefins selected from the group consisting of:        -   2,3,3-trifluoro-1-propene (CHF₂CF═CH₂);            1,1,2-trifluoro-1-propene (CH₃CF═CF₂);            1,2,3-trifluoro-1-propene (CH₂FCF═CF₂);            1,1,3-trifluoro-1-propene (CH₂FCH═CF₂);            1,3,3-trifluoro-1-propene (CHF₂CH═CHF);            1,1,1,2,3,4,4,4-octafluoro-2-butene (CF₃CF═CFCF₃);            1,1,2,3,3,4,4,4-octafluoro-1-butene (CF₃CF₂CF═CF₂);            1,1,1,2,4,4,4-heptafluoro-2-butene (CF₃CF═CHCF₃);            1,2,3,3,4,4,4-heptafluoro-1-butene (CHF═CFCF₂CF₃);            1,1,1,2,3,4,4-heptafluoro-2-butene (CHF₂CF═CFCF₃);            1,3,3,3-tetrafluoro-2-(trifluoromethyl)-1-propene            ((CF₃)₂C═CHF); 1,1,3,3,4,4,4-heptafluoro-1-butene            (CF₂═CHCF₂CF₃); 1,1,2,3,4,4,4-heptafluoro-1-butene            (CF₂═CFCHFCF₃); 1,1,2,3,3,4,4-heptafluoro-1-butene            (CF₂═CFCF₂CHF₂); 2,3,3,4,4,4-hexafluoro-1-butene            (CF₃CF₂CF═CH₂); 1,3,3,4,4,4-hexafluoro-1-butene            (CHF═CHCF₂CF₃); 1,2,3,4,4,4-hexafluoro-1-butene            (CHF═CFCHFCF₃); 1,2,3,3,4,4-hexafluoro-1-butene            (CHF═CFCF₂CHF₂); 1,1,2,3,4,4-hexafluoro-2-butene            (CHF₂CF═CFCHF₂); 1,1,1,2,3,4-hexafluoro-2-butene            (CH₂FCF═CFCF₃); 1,1,1,2,4,4-hexafluoro-2-butene            (CHF₂CH═CFCF₃); 1,1,1,3,4,4-hexafluoro-2-butene            (CF₃CH═CFCHF₂); 1,1,2,3,3,4-hexafluoro-1-butene            (CF₂═CFCF₂CH₂F); 1,1,2,3,4,4-hexafluoro-1-butene            (CF₂═CFCHFCHF₂);            3,3,3-trifluoro-2-(trifluoromethyl)-1-propene (CH₂═C(CF₃)₂);            1,1,1,2,4-pentafluoro-2-butene (CH₂FCH═CFCF₃);            1,1,1,3,4-pentafluoro-2-butene (CF₃CH═CFCH₂F);            3,3,4,4,4-pentafluoro-1-butene (CF₃CF₂CH═CH₂);            1,1,1,4,4-pentafluoro-2-butene (CHF₂CH═CHCF₃);            1,1,1,2,3-pentafluoro-2-butene (CH₃CF═CFCF₃);            2,3,3,4,4-pentafluoro-1-butene (CH₂═CFCF₂CHF₂);            1,1,2,4,4-pentafluoro-2-butene (CHF₂CF═CHCHF₂);            1,1,2,3,3-pentafluoro-1-butene (CH₃CF₂CF═CF₂);            1,1,2,3,4-pentafluoro-2-butene (CH₂FCF═CFCHF₂);            1,1,3,3,3-pentafluoro-2-methyl-1-propene (CF₂═C(CF₃)(CH₃));            2-(difluoromethyl)-3,3,3-trifluoro-1-propene            (CH₂═C(CHF₂)(CF₃)); 2,3,4,4,4-pentafluoro-1-butene            (CH₂═CFCHFCF₃); 1,2,4,4,4-pentafluoro-1-butene            (CHF═CFCH₂CF₃); 1,3,4,4,4-pentafluoro-1-butene            (CHF═CHCHFCF₃); 1,3,3,4,4-pentafluoro-1-butene            (CHF═CHCF₂CHF₂); 1,2,3,4,4-pentafluoro-1-butene            (CHF═CFCHFCHF₂); 3,3,4,4-tetrafluoro-1-butene            (CH₂═CHCF₂CHF₂); 1,1-difluoro-2-(difluoromethyl)-1-propene            (CF₂═C(CHF₂)(CH₃)); 1,3,3,3-tetrafluoro-2-methyl-1-propene            (CHF═C(CF₃)(CH₃)); 3,3-difluoro-2-(difluoromethyl)-1-propene            (CH₂═C(CHF₂)₂); 1,1,1,2-tetrafluoro-2-butene (CF₃CF═CHCH₃);            1,1,1,3-tetrafluoro-2-butene (CH₃CF═CHCF₃);            1,1,1,2,3,4,4,5,5,5-decafluoro-2-pentene (CF₃CF═CFCF₂CF₃);            1,1,2,3,3,4,4,5,5,5-decafluoro-1-pentene (CF₂═CFCF₂CF₂CF₃);            1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-2-butene            ((CF₃)₂C═CHCF₃); 1,1,1,2,4,4,5,5,5-nonafluoro-2-pentene            (CF₃CF═CHCF₂CF₃); 1,1,1,3,4,4,5,5,5-nonafluoro-2-pentene            (CF₃CH═CFCF₂CF₃); 1,2,3,3,4,4,5,5,5-nonafluoro-1-pentene            (CHF═CFCF₂CF₂CF₃); 1,1,3,3,4,4,5,5,5-nonafluoro-1-pentene            (CF₂═CHCF₂CF₂CF₃); 1,1,2,3,3,4,4,5,5-nonafluoro-1-pentene            (CF₂═CFCF₂CF₂CHF₂); 1,1,2,3,4,4,5,5,5-nonafluoro-2-pentene            (CHF₂CF═CFCF₂CF₃); 1,1,1,2,3,4,4,5,5-nonafluoro-2-pentene            (CF₃CF═CFCF₂CHF₂); 1,1,1,2,3,4,5,5,5-nonafluoro-2-pentene            (CF₃CF═CFCHFCF₃);            1,2,3,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene            (CHF═CFCF(CF₃)₂);            1,1,2,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene            (CF₂═CFCH(CF₃)₂);            1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-2-butene            (CF₃CH═C(CF₃)₂);            1,1,3,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene            (CF₂═CHCF(CF₃)₂); 2,3,3,4,4,5,5,5-octafluoro-1-pentene            (CH₂═CFCF₂CF₂CF₃); 1,2,3,3,4,4,5,5-octafluoro-1-pentene            (CHF═CFCF₂CF₂CHF₂);            3,3,4,4,4-pentafluoro-2-(trifluoromethyl)-1-butene            (CH₂═C(CF₃)CF₂CF₃);            1,1,4,4,4-pentafluoro-3-(trifluoromethyl)-1-butene            (CF₂═CHCH(CF₃)₂);            1,3,4,4,4-pentafluoro-3-(trifluoromethyl)-1-butene            (CHF═CHCF(CF₃)₂);            1,1,4,4,4-pentafluoro-2-(trifluoromethyl)-1-butene            (CF₂═C(CF₃)CH₂CF₃);            3,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene            ((CF₃)₂CFCH═CH₂); 3,3,4,4,5,5,5-heptafluoro-1-pentene            (CF₃CF₂CF₂CH═CH₂); 2,3,3,4,4,5,5-heptafluoro-1-pentene            (CH₂═CFCF₂CF₂CHF₂); 1,1,3,3,5,5,5-heptafluoro-1-butene            (CF₂═CHCF₂CH₂CF₃);            1,1,1,2,4,4,4-heptafluoro-3-methyl-2-butene            (CF₃CF═C(CF₃)(CH₃));            2,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene            (CH₂═CFCH(CF₃)₂);            1,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene            (CHF═CHCH(CF₃)₂);            1,1,1,4-tetrafluoro-2-(trifluoromethyl)-2-butene            (CH₂FCH═C(CF₃)₂);            1,1,1,3-tetrafluoro-2-(trifluoromethyl)-2-butene            (CH₃CF═C(CF₃)₂);            1,1,1-trifluoro-2-(trifluoromethyl)-2-butene            ((CF₃)₂C═CHCH₃); 3,4,4,5,5,5-hexafluoro-2-pentene            (CF₃CF₂CF═CHCH₃); 1,1,1,4,4,4-hexafluoro-2-methyl-2-butene            (CF₃C(CH₃)═CHCF₃); 3,3,4,5,5,5-hexafluoro-1-pentene            (CH₂═CHCF₂CHFCF₃);            4,4,4-trifluoro-3-(trifluoromethyl)-1-butene            (CH₂═C(CF₃)CH₂CF₃);            1,1,2,3,3,4,4,5,5,6,6,6-dodecafluoro-1-hexene            (CF₃(CF₂)₃CF═CF₂);            1,1,1,2,2,3,4,5,5,6,6,6-dodecafluoro-3-hexene            (CF₃CF₂CF═CFCF₂CF₃);            1,1,1,4,4,4-hexafluoro-2,3-bis(trifluoromethyl)-2-butene            ((CF₃)₂C═C(CF₃)₂);            1,1,1,2,3,4,5,5,5-nonafluoro-4-(trifluoromethyl)-2-pentene            ((CF₃)₂CFCF═CFCF₃);            1,1,1,4,4,5,5,5-octafluoro-2-(trifluoromethyl)-2-pentene            ((CF₃)₂C═CHC₂F₅);            1,1,1,3,4,5,5,5-octafluoro-4-(trifluoromethyl)-2-pentene            ((CF₃)₂CFCF═CHCF₃); 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene            (CF₃CF₂CF₂CF₂CH═CH₂);            4,4,4-trifluoro-3,3-bis(trifluoromethyl)-1-butene            (CH₂═CHC(CF₃)₃);            1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-3-methyl-2-butene            ((CF₃)₂C═C(CH₃)(CF₃));            2,3,3,5,5,5-hexafluoro-4-(trifluoromethyl)-1-pentene            (CH₂═CFCF₂CH(CF₃)₂);            1,1,1,2,4,4,5,5,5-nonafluoro-3-methyl-2-pentene            (CF₃CF═C(CH₃)CF₂CF₃);            1,1,1,5,5,5-hexafluoro-4-(trifluoromethyl)-2-pentene            (CF₃CH═CHCH(CF₃)₂); 3,4,4,5,5,6,6,6-octafluoro-2-hexene            (CF₃CF₂CF₂CF═CHCH₃); 3,3,4,4,5,5,6,6-octafluoro 1-hexene            (CH₂═CHCF₂CF₂CF₂CHF₂);            1,1,1,4,4-pentafluoro-2-(trifluoromethyl)-2-pentene            ((CF₃)₂C═CHCF₂CH₃);            4,4,5,5,5-pentafluoro-2-(trifluoromethyl)-1-pentene            (CH₂═C(CF₃)CH₂C₂F₅);            3,3,4,4,5,5,5-heptafluoro-2-methyl-1-pentene            (CF₃CF₂CF₂C(CH₃)═CH₂); 4,4,5,5,6,6,6-heptafluoro-2-hexene            (CF₃CF₂CF₂CH═CHCH₃); 4,4,5,5,6,6,6-heptafluoro-1-hexene            (CH₂═CHCH₂CF₂C₂F₅); 1,1,1,2,2,3,4-heptafluoro-3-hexene            (CF₃CF₂CF═CFC₂H₅);            4,5,5,5-tetrafluoro-4-(trifluoromethyl)-1-pentene            (CH₂═CHCH₂CF(CF₃)₂);            1,1,1,2,5,5,5-heptafluoro-4-methyl-2-pentene            (CF₃CF═CHCH(CF₃)(CH₃));            1,1,1,3-tetrafluoro-2-(trifluoromethyl)-2-pentene            ((CF₃)₂C═CFC₂H₅);            1,1,1,2,3,4,4,5,5,6,6,7,7,7-tetradecafluoro-2-heptene            (CF₃CF═CFCF₂CF₂C₂F₅);            1,1,1,2,2,3,4,5,5,6,6,7,7,7-tetradecafluoro-3-heptene            (CF₃CF₂CF═CFCF₂C₂F₅);            1,1,1,3,4,4,5,5,6,6,7,7,7-tridecafluoro-2-heptene            (CF₃CH═CFCF₂CF₂C₂F₅);            1,1,1,2,4,4,5,5,6,6,7,7,7-tridecafluoro-2-heptene            (CF₃CF═CHCF₂CF₂C₂F₅);            1,1,1,2,2,4,5,5,6,6,7,7,7-tridecafluoro-3-heptene            (CF₃CF₂CH═CFCF₂C₂F₅);            1,1,1,2,2,3,5,5,6,6,7,7,7-tridecafluoro-3-heptene            (CF₃CF₂CF═CHCF₂C₂F₅); CF₂═CFOCF₂CF₃ (PEVE) and CF₂═CFOCF₃            (PMVE).

In yet another embodiment, the refrigerant can be a compositioncomprising the fluoroolefin as defined above with a flammablerefrigerant as described in U.S. Provisional Application No. 60/732,581,which is incorporated in its entirety as a part hereof for all purposes.Flammable refrigerants comprise any compound, which may be demonstratedto propagate a flame under specified conditions of temperature, pressureand composition when mixed with air. Flammable refrigerants may beidentified by testing under conditions specified by ASHRAE (AmericanSociety of Heating, Refrigerating and Air-Conditioning Engineers, Inc.)Standard 34-2001, under ASTM (American Society of Testing and Materials)E681-01, with an electronic ignition source. Such tests of flammabilityare conducted with the refrigerant at 101 kPa (14.7 psia) and aspecified temperature (typically 100° C. (212° F.), or room temperature,that being about 23° C. (73° F.) at various concentrations in air inorder to determine the lower flammability limit (LFL) and upperflammability limit (UFL) of the test compound in air. Flammablerefrigerants include hydrofluorocarbons, such as difluoromethane(HFC-32), fluorolefins, such as 1,2,3,3-tetrafluoro-1-propene(HFC-1234ye), fluoroethers, such as C₄F₉OC₂H₅, hydrocarbon ethers, suchas dimethyl ether, hydrocarbons, such as propane, ammonia, andcombinations thereof. One example of a refrigerant compositioncomprising a fluoroolefin refrigerant with a flammable refrigerant is arefrigerant composition comprising about 99.0 weight percent to about63.0 weight percent C₃HF₅ (HFC-1225ye) and about 1.0 weight percent toabout 37.0 weight percent HFC-32.

Refrigerants useful for the invention also include compositionscomprising pentafluoroethane (R-125), 1,1,1,2-tetrafluoroethane(R-134a), and at least two hydrocarbons each having eight or fewercarbon atoms, as described in U.S. Provisional Application No.60/876,406, which is incorporated in its entirety as a part hereof forall purposes. In some embodiments, the hydrocarbon is C₄ to C₈hydrocarbon, such as butanes, pentanes, hexanes, heptanes, octanes, C₄to C₈ alkenes, C₄ to C₈ cycloalkanes, or mixtures thereof. In certainembodiments, the hydrocarbon components consist of n-butane (R-600) andn-pentane (R-601). In some embodiments, the pentafluoroethane is used atfrom about 13% to about 20% by weight of the composition, and in someembodiments, the 1,1,1,2-tetrafluoroethane is used at from about 70% toabout 80% by weight of the composition. In some embodiments, thehydrocarbon component is used at from about 1% to about 6% by weight.

Refrigerants useful in this invention can be obtained commercially, orcan be synthesized by the methods described in U.S. ProvisionalApplication No. 60/732,581.

An ionic liquid useful as a lubricant herein can in principle be anyionic liquid that absorbs a refrigerant such as a hydrofluorocarbon orCO₂. Ideally, for maximum oil return to the compressor, the ionicliquid-based lubricant should have high solubility for the refrigerantand good friction/wear characteristics.

Ionic liquids are organic compounds that are liquid at room temperature(approximately 25° C.). They differ from most salts in that they havevery low melting points, they tend to be liquid over a wide temperaturerange, and have been shown to have high heat capacities. Ionic liquidshave essentially no vapor pressure, and they can either be neutral,acidic or basic. The properties of an ionic liquid can be tailored byvarying the cation and anion. A cation or anion of an ionic liquiduseful for the present invention can in principle be any cation or anionsuch that the cation and anion together form an organic salt that isliquid at or below about 100° C.

Many ionic liquids are formed by reacting a nitrogen-containingheterocyclic ring, preferably a heteroaromatic ring, with an alkylatingagent (for example, an alkyl halide) to form a quaternary ammonium salt,and performing ion exchange or other suitable reactions with variousLewis acids or their conjugate bases to form the ionic liquid. Examplesof suitable heteroaromatic rings include substituted pyridines,imidazole, substituted imidazole, pyrrole and substituted pyrroles.These rings can be alkylated with virtually any straight, branched orcyclic C₁₋₂₀ alkyl group, but preferably, the alkyl groups are C₁₋₁₆groups, since groups larger than this may produce low melting solidsrather than ionic liquids. Various triarylphosphines, thioethers andcyclic and non-cyclic quaternary ammonium salts may also been used forthis purpose. Counterions that may be used include chloroaluminate,bromoaluminate, gallium chloride, tetrafluoroborate, tetrachloroborate,hexafluorophosphate, nitrate, trifluoromethane sulfonate,methylsulfonate, p-toluenesulfonate, hexafluoroantimonate,hexafluoroarsenate, tetrachloroaluminate, tetrabromoaluminate,perchlorate, hydroxide anion, copper dichloride anion, iron trichlorideanion, zinc trichloride anion, as well as various lanthanum, potassium,lithium, nickel, cobalt, manganese, and other metal-containing anions.

Ionic liquids may also be synthesized by salt metathesis, by anacid-base neutralization reaction or by quaternizing a selectednitrogen-containing compound; or they may be obtained commercially fromseveral companies such as Merck (Darmstadt, Germany) or BASF (MountOlive, N.J.).

Representative examples of ionic liquids useful herein included amongthose that are described in sources such as J. Chem. Tech. Biotechnol.,68:351-356 (1997); Chem. Ind., 68:249-263 (1996); J. Phys. CondensedMatter, 5: (supp 34B):B99-B106 (1993); Chemical and Engineering News,Mar. 30, 1998, 32-37; J. Mater. Chem., 8:2627-2636 (1998); Chem. Rev.,99:2071-2084 (1999); and WO 05/113,702 (and references therein cited).In one embodiment, a library, i.e. a combinatorial library, of ionicliquids may be prepared, for example, by preparing various alkylderivatives of a quaternary ammonium cation, and varying the associatedanions. The acidity of the ionic liquids can be adjusted by varying themolar equivalents and type and combinations of Lewis acids.

In another embodiment of the invention, ionic liquids suitable for useherein may have cations selected from the following Formulae:

wherein R¹, R², R³, R⁴R⁵ and R⁶ are independently selected from thegroup consisting of:

-   -   (i) H    -   (ii) halogen    -   (iii) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or        cyclic alkane or alkene, optionally substituted with at least        one member selected from the group consisting of Cl, Br, F, I,        OH, NH₂ and SH;    -   (iv) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or        cyclic alkane or alkene comprising one to three heteroatoms        selected from the group consisting of O, N, Si and S, and        optionally substituted with at least one member selected from        the group consisting of Cl, Br, F, I, OH, NH₂ and SH;    -   (v) C₆ to C₂₀ unsubstituted aryl, or C₃ to C₂₅ unsubstituted        heteroaryl having one to three heteroatoms independently        selected from the group consisting of O, N, Si and S; and    -   (vi) C₆ to C₂₅ substituted aryl, or C₃ to C₂₅ substituted        heteroaryl having one to three heteroatoms independently        selected from the group consisting of O, N, Si and S; and        wherein said substituted aryl or substituted heteroaryl has one        to three substituents independently selected from the group        consisting of:        -   (1) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or            cyclic alkane or alkene, optionally substituted with at            least one member selected from the group consisting of Cl,            Br, F I, OH, NH₂ and SH,        -   (2) OH,        -   (3) NH₂, and        -   (4) SH;            R⁷, R⁸, R⁹, and R¹⁰ are independently selected from the            group consisting of:    -   (vii) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or        cyclic alkane or alkene, optionally substituted with at least        one member selected from the group consisting of Cl, Br, F, I,        OH, NH₂ and SH;    -   (viii) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or        cyclic alkane or alkene comprising one to three heteroatoms        selected from the group consisting of O, N, Si and S, and        optionally substituted with at least one member selected from        the group consisting of Cl, Br, F, I, OH, NH₂ and SH;    -   (ix) C₆ to C₂₅ unsubstituted aryl, or C₃ to C₂₅ unsubstituted        heteroaryl having one to three heteroatoms independently        selected from the group consisting of O, N, Si and S; and    -   (x) C₆ to C₂₅ substituted aryl, or C₃ to C₂₅ substituted        heteroaryl having one to three heteroatoms independently        selected from the group consisting of O, N, Si and S; and        wherein said substituted aryl or substituted heteroaryl has one        to three substituents independently selected from the group        consisting of:        -   (1) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or            cyclic alkane or alkene, optionally substituted with at            least one member selected from the group consisting of Cl,            Br, F, I, OH, NH₂ and SH,        -   (2) OH,        -   (3) NH₂, and        -   (4) SH; and            wherein optionally at least two of R¹, R², R³, R⁴, R⁵, R⁶,            R⁷, R⁸, R⁹, and R¹⁰ can together form a cyclic or bicyclic            alkanyl or alkenyl group.

In another embodiment, ionic liquids useful for the invention comprisefluorinated cations wherein at least one member selected from R¹, R²,R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹ and R¹⁰ comprises F⁻.

In another embodiment, ionic liquids have anions selected from the groupconsisting of [CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻,[CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO₄]3−, [HPO₄]²⁻, [H₂PO₄]⁻,[HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻, SCN⁻; and preferably any fluorinatedanion. Fluorinated anions of the invention include [BF₄]⁻, [PF₆]⁻,[SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻, [CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻,[(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻, [(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻,[CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻, [CF₃CFHOCF₂CF₂SO₃]⁻,[CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂₁CF₂OCF₂CF₂SO₃]⁻, [CF₃CF₂OCF₂CF₂SO₃]⁻,[(CF₂HCF₂SO₂)₂N]⁻, [(CF₃CFHCF₂SO₂)₂N]⁻; and F⁻. In another embodiment,ionic liquids comprise a cation selected from the group consisting ofpyridinium, pyridazinium, pyrimidinium, pyrazinium, imidazolium,pyrazolium, thiazolium, oxazolium, triazolium, phosphonium, and ammoniumas defined above; and an anion selected from the group consisting of[CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻,[NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻, [H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻,Cl⁻, Br⁻, I⁻, SCN⁻; and any fluorinated anion. In yet anotherembodiment, ionic liquids comprise a cation selected from the groupconsisting of pyridinium, pyridazinium, pyrimidinium, pyrazinium,imidazolium, pyrazolium, thiazolium, oxazolium, triazolium, phosphonium,and ammonium as defined above; and an anion selected from the groupconsisting of [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻,[CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻,[(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻,[CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻,[CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N]⁻, [(CF₃CFHCF₂SO₂)₂N]⁻, and F⁻.

In another embodiment, ionic liquids comprise a cation selected from thegroup consisting of pyridinium, pyridazinium, pyrimidinium, pyrazinium,imidazolium, pyrazolium, thiazolium, oxazolium, triazolium, phosphonium,and ammonium as defined above, wherein at least one member selected fromR¹, R², R³, R⁴, R⁵, R⁶, R⁷R⁸, R⁹, and R¹⁰ comprises F; and an anionselected from the group consisting of [CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻,[C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻, [SO₄]²⁻,[PO₄]³⁻, [HPO₄]²⁻, [H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻, SCN⁻; andany fluorinated anion. In still another embodiment, ionic liquidscomprise a cation selected from the group consisting of pyridinium,pyridazinium, pyrimidinium, pyrazinium, imidazolium, pyrazolium,thiazolium, oxazolium, triazolium, phosphonium, and ammonium as definedabove, wherein at least one member selected from R¹, R², R³, R⁴, R⁵, R⁶,R⁷, R⁸, R⁹, and R¹⁰ comprises F⁻; and an anion selected from the groupconsisting of [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻,[CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻,[(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻,[CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂₁CF₂OCF₂CF₂SO₃]⁻,[CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N]⁻, [(CF₃CFHCF₂SO₂)₂N]⁻, and F⁻.

In another embodiment, an ionic liquid comprises1-butyl-3-methylimidazolium, 1,2-dimethyl-3-propylimidazolium,1-octyl-3-methylimidazolium, 1,3-dioctylimidazolium,1-ethyl-3-methylimidazolium, 1-dodecyl-3-methylimidazolium,1-heptyl-3-methylimidazolium, 3-methyl-1-propylpyridinium,1-butyl-3-methylpyridinium, tetradecyl(trihexyl)phosphonium, ortributyl(tetradecyl)phosphonium as the cation and an anion selected fromthe group consisting of [CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻,[AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻,[H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻, SCN⁻, [BF₄]⁻, [PF₆]⁻,[SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻, [CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻,[(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻, [(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻,[CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻, [CF₃CFHOCF₂CF₂SO₃]⁻,[CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻, [CF₃CF₂OCF₂CF₂SO₃]⁻,[(CF₂HCF₂SO₂)₂N]⁻, and [(CF₃CFHCF₂SO₂)₂N]⁻.

In an even more specific embodiment, the at least one ionic liquid isselected from the group consisting of 1-butyl-3-methylimidazoliumhexafluorophosphate [bmim][PF₆], 1-butyl-3-methylimidazoliumtetrafluoroborate [bmim][BF₄], 1,2-dimethyl-3-propylimidazoliumtris(trifluoromethylsulfonyl)methide [dmpim][TMeM],1-octyl-3-methylimidazolium iodide [omim][I], 1,3-dioctylimidazoliumiodide [doim][I], 1-ethyl-3-methylimidazoliumbis(pentafluoroethylsulfonyl)imide [emim][BEI],1,2-dimethyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide[dmpim][BMeI], 3-methyl-1-propylpyridiniumbis(trifluoromethylsulfonyl)imide [pmpy][BMeI],1-ethyl-3-methylimidazolium hexafluorophosphate [emim][PF₆],1-ethyl-3-methylimidazolium bis(trifluoroethylsulfonyl)imide[emim][BMeI], 1-butyl-3-methylpyridiniumbis(trifluoromethylsulfonyl)imide [bmpy][BMeI],1-ethyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[emim][TFES], 1-butyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate [bmim][TFES],1-dodecyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[dmim][TFES], 1-heptyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate [hmim][TFES],1-butyl-3-methylimidazolium acetate [bmim][Ac],1-butyl-3-methylimidazolium2-(1,2,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate[bmim][FS], 1-butyl-3-methylimidazolium1,1,2,3,3,3-hexafluoropropanesulfonate [bmim][HFPS],1-butyl-3-methylimidazolium methyl sulfonate [bmim][MeSO₄],1-butyl-3-methylimidazolium thiocyanate [bmim][SCN],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES],1-ethyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide[emim][BEI], 1-butyl-3-methylimidazolium1,1,2,3,3-hexafluoropropanesulfonate [bmim][HFPS],tetradecyl(trihexyl)phosphonium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [6,6,6,14-P][TPES],tributyl(tetradecyl)phosphonium 1,1,2,3,3,3-hexafluoropropanesulfonate[4,4,4,14-P][HFPS].

Mixtures of ionic liquids may also be useful as lubricants.

In another embodiment, vapor compression systems herein may utilize atleast one refrigerant selected from the group consisting of CHClF₂(R-22), CHF₃ (R-23), CH₂F₂ (R-32), CH₃F (R-41), CHF₂CF₃ (R-125), CH₂FCF₃(R-134a), CHF₂OCHF₂ (E-134), CH₃CClF₂ (R-142b), CH₃CF₃ (R-143a), CH₃CHF₂(R-152a), CH₃CH₂F (R-161), CH₃OCH₃ (E170), CF₃CF₂CF₃ (R-218), CF₃CHFCF₃(R-227ea), CF₃CH₂CF₃ (R-236fa), CH₂FCF₂CHF₂ (R-245ca), CHF₂CH₂CF₃(R-245fa), CH₃CH₂CH₃ (R-290), CH₃CH₂CH₂CH₃ (R-600), CH(CH₃)₂CH₃(R-600a), CH₃CH₂CH₂CH₂CH₃ (R-601), (CH₃)₂CHCH₂CH₃ (R-601a),CH₃CH₂OCH₂CH₃ (R-610), NH₃, CO₂, and CH₃CH═CH₂; and at least one ionicliquid comprising pyridinium, pyridazinium, pyrimidinium, pyrazinium,imidazolium, pyrazolium, thiazolium, oxazolium, triazolium, phosphonium,or ammonium as the cation and an anion selected from the groupconsisting of [CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻,[CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻, [H₂PO₄]⁻,[HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻, SCN⁻, [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻,[CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻, [CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻,[(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻, [(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻,[CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻, [CF₃CFHOCF₂CF₂SO₃]⁻,[CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻, [CF₃CF₂OCF₂CF₂SO₃]⁻,[(CF₂HCF₂SO₂)₂N]⁻, and [(CF₃CFHCF₂SO₂)₂N]⁻.

Vapor compression systems may also utilize at least one refrigerantblend selected from the group consisting of R-404A; R-407A; R-407B;R-407C; R-407D; R-407E; R-410A; R-410B; R-413A; 417A; R-419A; R-420A;80.6% R-134a and 19.4% R-142b (by weight); R-421A; R-421B; R-422A;R-422B; R-422C; R-422D; R423A; R-424A; R-425A; R-426A; R-427A; 2.0%R-32, 41.0% R-125, 50.0% R-143a and 7.0% R-134a (by weight); 10.0% R-32,33.0% R-125, 36.0% R-143a and 21.0% R-134a (by weight); R-428A; andR-507A; and at least one ionic liquid comprising pyridinium,pyridazinium, pyrimidinium, pyrazinium, imidazolium, pyrazolium,thiazolium, oxazolium, triazolium, phosphonium, or ammonium as thecation and an anion selected from the group consisting of [CH₃CO₂]⁻,[HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻,[NO₃]⁻, [SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻, [H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻, Cl⁻,Br⁻, I⁻, SCN⁻, [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻,[CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻,[(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻,[CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻,[CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N]⁻, and [(CF₃CFHCF₂SO₂)₂N]⁻.

Vapor compression systems may also utilize at least one refrigerantselected from the group consisting of trifluoromethane (HFC-23),difluoromethane (HFC-32), pentafluoroethane (HFC-125),1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoroethane(HFC-134a), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethane(HFC-152a), fluoroethane (HFC-161), R-404A, R-407C, R-410A, and CO₂; andat least one ionic liquid comprising pyridinium, pyridazinium,pyrimidinium, pyrazinium, imidazolium, pyrazolium, thiazolium,oxazolium, triazolium, phosphonium, or ammonium as the cation and ananion selected from the group consisting of [CH₃CO₂]⁻, [HSO₄]⁻,[CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻,[SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻, [H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻,SCN⁻, [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻,[CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻,[(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻,[CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻,[CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N]⁻, and [(CF₃CFHCF₂SO₂)₂N]⁻.

Vapor compression systems may also utilize at least one fluoroolefinrefrigerant selected from the group consisting of:

-   -   (i) fluoroolefins of the formula E- or Z-R¹CH═CHR², wherein R¹        and R² are, independently, C₁ to C₆ perfluoroalkyl groups, and        wherein the total number of carbons in the compound is at least        5;    -   (ii) cyclic fluoroolefins of the formula        cyclo-[CX═CY(CZW)_(n)-], wherein X, Y, Z, and W, independently,        are H or F, and n is an integer from 2 to 5; and    -   (iii) fluoroolefins selected from the group consisting of:

2,3,3-trifluoro-1-propene (CHF₂CF═CH₂); 1,1,2-trifluoro-1-propene(CH₃CF═CF₂); 1,2,3-trifluoro-1-propene (CH₂FCF═CF₂);1,1,3-trifluoro-1-propene (CH₂FCH═CF₂); 1,3,3-trifluoro-1-propene(CHF₂CH═CHF); 1,1,1,2,3,4,4,4-octafluoro-2-butene (CF₃CF═CFCF₃);1,1,2,3,3,4,4,4-octafluoro-1-butene (CF₃CF₂CF═CF₂);1,1,1,2,4,4,4-heptafluoro-2-butene (CF₃CF═CHCF₃);1,2,3,3,4,4,4-heptafluoro-1-butene (CHF═CFCF₂CF₃);1,1,1,2,3,4,4-heptafluoro-2-butene (CHF₂CF═CFCF₃);1,3,3,3-tetrafluoro-2-(trifluoromethyl)-1-propene ((CF₃)₂C═CHF);1,1,3,3,4,4,4-heptafluoro-1-butene (CF₂═CHCF₂CF₃);1,1,2,3,4,4,4-heptafluoro-1-butene (CF₂═CFCHFCF₃);1,1,2,3,3,4,4-heptafluoro-1-butene (CF₂═CFCF₂CHF₂);2,3,3,4,4,4-hexafluoro-1-butene (CF₃CF₂CF═CH₂);1,3,3,4,4,4-hexafluoro-1-butene (CHF═CHCF₂CF₃);1,2,3,4,4,4-hexafluoro-1-butene (CHF═CFCHFCF₃);1,2,3,3,4,4-hexafluoro-1-butene (CHF═CFCF₂CHF₂);1,1,2,3,4,4-hexafluoro-2-butene (CHF₂CF═CFCHF₂);1,1,1,2,3,4-hexafluoro-2-butene (CH₂FCF═CFCF₃);1,1,1,2,4,4-hexafluoro-2-butene (CHF₂CH═CFCF₃);1,1,1,3,4,4-hexafluoro-2-butene (CF₃CH═CFCHF₂);1,1,2,3,3,4-hexafluoro-1-butene (CF₂═CFCF₂CH₂F);1,1,2,3,4,4-hexafluoro-1-butene (CF₂═CFCHFCHF₂);3,3,3-trifluoro-2-(trifluoromethyl)-1-propene (CH₂═C(CF₃)₂);1,1,1,2,4-pentafluoro-2-butene (CH₂FCH═CFCF₃);1,1,1,3,4-pentafluoro-2-butene (CF₃CH═CFCH₂F);3,3,4,4,4-pentafluoro-1-butene (CF₃CF₂CH═CH₂);1,1,1,4,4-pentafluoro-2-butene (CHF₂CH═CHCF₃);1,1,1,2,3-pentafluoro-2-butene (CH₃CF═CFCF₃);2,3,3,4,4-pentafluoro-1-butene (CH₂═CFCF₂CHF₂);1,1,2,4,4-pentafluoro-2-butene (CHF₂CF═CHCHF₂);1,1,2,3,3-pentafluoro-1-butene (CH₃CF₂CF═CF₂);1,1,2,3,4-pentafluoro-2-butene (CH₂FCF═CFCHF₂);1,1,3,3,3-pentafluoro-2-methyl-1-propene (CF₂═C(CF₃)(CH₃));2-(difluoromethyl)-3,3,3-trifluoro-1-propene (CH₂═C(CHF₂)(CF₃));2,3,4,4,4-pentafluoro-1-butene (CH₂═CFCHFCF₃);1,2,4,4,4-pentafluoro-1-butene (CHF═CFCH₂CF₃);1,3,4,4,4-pentafluoro-1-butene (CHF═CHCHFCF₃);1,3,3,4,4-pentafluoro-1-butene (CHF═CHCF₂CHF₂);1,2,3,4,4-pentafluoro-1-butene (CHF═CFCHFCHF₂);3,3,4,4-tetrafluoro-1-butene (CH₂═CHCF₂CHF₂);1,1-difluoro-2-(difluoromethyl)-1-propene (CF₂═C(CHF₂)(CH₃));1,3,3,3-tetrafluoro-2-methyl-1-propene (CHF═C(CF₃)(CH₃));3,3-difluoro-2-(difluoromethyl)-1-propene (CH₂═C(CHF₂)₂);1,1,1,2-tetrafluoro-2-butene (CF₃CF═CHCH₃); 1,1,1,3-tetrafluoro-2-butene(CH₃CF═CHCF₃); 1,1,1,2,3,4,4,5,5,5-decafluoro-2-pentene(CF₃CF═CFCF₂CF₃); 1,1,2,3,3,4,4,5,5,5-decafluoro-1-pentene(CF₂═CFCF₂CF₂CF₃); 1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-2-butene((CF₃)₂C═CHCF₃); 1,1,1,2,4,4,5,5,5-nonafluoro-2-pentene(CF₃CF═CHCF₂CF₃); 1,1,1,3,4,4,5,5,5-nonafluoro-2-pentene(CF₃CH═CFCF₂CF₃); 1,2,3,3,4,4,5,5,5-nonafluoro-1-pentene(CHF═CFCF₂CF₂CF₃); 1,1,3,3,4,4,5,5,5-nonafluoro-1-pentene(CF₂═CHCF₂CF₂CF₃); 1,1,2,3,3,4,4,5,5-nonafluoro-1-pentene(CF₂═CFCF₂CF₂CHF₂); 1,1,2,3,4,4,5,5,5-nonafluoro-2-pentene(CHF₂CF═CFCF₂CF₃); 1,1,1,2,3,4,4,5,5-nonafluoro-2-pentene(CF₃CF═CFCF₂CHF₂); 1,1,1,2,3,4,5,5,5-nonafluoro-2-pentene (CF₃CF═CFCHFCF₃); 1,2,3,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene(CHF═CFCF(CF₃)₂); 1,1,2,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene(CF₂═CFCH(CF₃)₂); 1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-2-butene(CF₃ CH═C(CF₃)₂); 1,1,3,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene(CF₂═CHCF(CF₃)₂); 2,3,3,4,4,5,5,5-octafluoro-1-pentene(CH₂═CFCF₂CF₂CF₃); 1,2,3,3,4,4,5,5-octafluoro-1-pentene(CHF═CFCF₂CF₂CHF₂); 3,3,4,4,4-pentafluoro-2-(trifluoromethyl)-1-butene(CH₂═C(CF₃)CF₂CF₃); 1,1,4,4,4-pentafluoro-3-(trifluoromethyl)-1-butene(CF₂═CHCH(CF₃)₂); 1,3,4,4,4-pentafluoro-3-(trifluoromethyl)-1-butene(CHF═CHCF(CF₃)₂); 1,1,4,4,4-pentafluoro-2-(trifluoromethyl)-1-butene(CF₂═C(CF₃)CH₂CF₃); 3,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene((CF₃)₂CFCH═CH₂); 3,3,4,4,5,5,5-heptafluoro-1-pentene (CF₃CF₂CF₂CH═CH₂);2,3,3,4,4,5,5-heptafluoro-1-pentene (CH₂═CFCF₂CF₂CHF₂);1,1,3,3,5,5,5-heptafluoro-1-butene (CF₂═CHCF₂CH₂CF₃);1,1,1,2,4,4,4-heptafluoro-3-methyl-2-butene (CF₃CF═C(CF₃)(CH₃));2,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene (CH₂═CFCH(CF₃)₂);1,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene (CHF═CHCH(CF₃)₂);1,1,1,4-tetrafluoro-2-(trifluoromethyl)-2-butene (CH₂FCH═C(CF₃)₂);1,1,1,3-tetrafluoro-2-(trifluoromethyl)-2-butene (CH₃CF═C(CF₃)₂);1,1,1-trifluoro-2-(trifluoromethyl)-2-butene ((CF₃)₂C═CHCH₃);3,4,4,5,5,5-hexafluoro-2-pentene (CF₃CF₂CF═CHCH₃);1,1,1,4,4,4-hexafluoro-2-methyl-2-butene (CF₃C(CH₃)═CHCF₃);3,3,4,5,5,5-hexafluoro-1-pentene (CH₂═CHCF₂CHFCF₃);4,4,4-trifluoro-3-(trifluoromethyl)-1-butene (CH₂═C(CF₃)CH₂CF₃);1,1,2,3,3,4,4,5,5,6,6,6-dodecafluoro-1-hexene (CF₃(CF₂)₃CF═CF₂);1,1,1,2,2,3,4,5,5,6,6,6-dodecafluoro-3-hexene (CF₃CF₂CF═CFCF₂CF₃);1,1,1,4,4,4-hexafluoro-2,3-bis(trifluoromethyl)-2-butene((CF₃)₂C═C(CF₃)₂);1,1,1,2,3,4,5,5,5-nonafluoro-4-(trifluoromethyl)-2-pentene((CF₃)₂CFCF═CFCF₃);1,1,1,4,4,5,5,5-octafluoro-2-(trifluoromethyl)-2-pentene((CF₃)₂C═CHC₂F₅);1,1,1,3,4,5,5,5-octafluoro-4-(trifluoromethyl)-2-pentene((CF₃)₂CFCF═CHCF₃); 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene(CF₃CF₂CF₂CF₂CH═CH₂); 4,4,4-trifluoro-3,3-bis(trifluoromethyl)-1-butene(CH₂═CHC(CF₃)₃);1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-3-methyl-2-butene((CF₃)₂C═C(CH₃)(CF₃));2,3,3,5,5,5-hexafluoro-4-(trifluoromethyl)-1-pentene(CH₂═CFCF₂CH(CF₃)₂); 1,1,1,2,4,4,5,5,5-nonafluoro-3-methyl-2-pentene(CF₃ CF═C(CH₃)CF₂CF₃);1,1,1,5,5,5-hexafluoro-4-(trifluoromethyl)-2-pentene (CF₃CH═CHCH(CF₃)₂);3,4,4,5,5,6,6,6-octafluoro-2-hexene (CF₃CF₂CF₂CF═CHCH₃);3,3,4,4,5,5,5,6,6-octafluoro 1-hexene (CH₂═CHCF₂CF₂CF₂CHF₂);1,1,1,4,4-pentafluoro-2-(trifluoromethyl)-2-pentene ((CF₃)₂C═CHCF₂CH₃);4,4,5,5,5-pentafluoro-2-(trifluoromethyl)-1-pentene (CH₂═C(CF₃)CH₂C₂F₅);3,3,4,4,5,5,5-heptafluoro-2-methyl-1-pentene (CF₃CF₂CF₂C(CH₃)═CH₂);4,4,5,5,6,6,6-heptafluoro-2-hexene (CF₃CF₂CF₂CH═CHCH₃);4,4,5,5,6,6,6-heptafluoro-1-hexene (CH₂═CHCH₂CF₂C₂F₅);1,1,1,2,2,3,4-heptafluoro-3-hexene (CF₃CF₂CF═CFC₂H₅);4,5,5,5-tetrafluoro-4-(trifluoromethyl)-1-pentene (CH₂═CHCH₂CF(CF₃)₂);1,1,1,2,5,5,5-heptafluoro-4-methyl-2-pentene (CF₃CF═CHCH(CF₃)(CH₃));1,1,1,3-tetrafluoro-2-(trifluoromethyl)-2-pentene ((CF₃)₂C═CFC₂H₅);1,1,1,2,3,4,4,5,5,6,6,7,7,7-tetradecafluoro-2-heptene(CF₃CF═CFCF₂CF₂C₂F₅);1,1,1,2,2,3,4,5,5,6,6,7,7,7-tetradecafluoro-3-heptene(CF₃CF₂CF═CFCF₂C₂F₅); 1,1,1,3,4,4,5,5,6,6,7,7,7-tridecafluoro-2-heptene(CF₃CH═CFCF₂CF₂C₂F₅); 1,1,1,2,4,4,5,5,6,6,7,7,7-tridecafluoro-2-heptene(CF₃CF═CHCF₂CF₂C₂F₅); 1,1,1,2,2,4,5,5,6,6,7,7,7-tridecafluoro-3-heptene(CF₃CF₂CH═CFCF₂C₂F₅); 1,1,1,2,2,3,5,5,6,6,7,7,7-tridecafluoro-3-heptene(CF₃CF₂CF═CHCF₂C₂F₅); CF₂═CFOCF₂CF₃ (PEVE) and CF₂═CFOCF₃ (PMVE); and atleast one ionic liquid comprising pyridinium, pyridazinium,pyrimidinium, pyrazinium, imidazolium, pyrazolium, thiazolium,oxazolium, triazolium, phosphonium, or ammonium as the cation and ananion selected from the group consisting of [CH₃CO₂]⁻, [HSO₄]⁻,[CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻,[SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻, [H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻,SCN⁻, [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻,[CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻,[(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻,[CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻,[CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N]⁻, and [(CF₃CFHCF₂SO₂)₂N]⁻.

Vapor compression systems may also utilize at least one refrigerantcomprising pentafluoroethane (R-125), 1,1,1,2-tetrafluoroethane(R-134a), and at least two hydrocarbons each having eight or fewercarbon atoms, wherein said at least two hydrocarbons can be C₄ to C₈hydrocarbons, and more specifically n-butane and n-pentane; and at leastone ionic liquid comprising pyridinium, pyridazinium, pyrimidinium,pyrazinium, imidazolium, pyrazolium, thiazolium, oxazolium, triazolium,phosphonium, or ammonium as the cation and an anion selected from thegroup consisting of [CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻,[AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻,[H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻, SCN⁻, [BF₄]⁻, [PF₆]⁻,[SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻, [CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻,[(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻, [(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻,[CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻, [CF₃CFHOCF₂CF₂SO₃]⁻,[CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻, [CF₃CF₂OCF₂CF₂SO₃]⁻,[(CF₂HCF₂SO₂)₂N]⁻, and [(CF₃CFHCF₂SO₂)₂N]⁻.

Vapor compression systems may also utilize at least one refrigerantselected from the group consisting of trifluoromethane (HFC-23),difluoromethane (HFC-32), pentafluoroethane (HFC-125),1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoroethane(HFC-134a), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethane(HFC-152a), fluoroethane (HFC-161), R-404A, R-407C, HFC-410A, and CO₂;and at least one ionic liquid selected from the group consisting of1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆],1-butyl-3-methylimidazolium tetrafluoroborate [bmim][BF₄],1,2-dimethyl-3-propylimidazolium tris(trifluoromethylsulfonyl)methide[dmpim][TMeM], 1-octyl-3-methylimidazolium iodide [omim][I],1,3-dioctylimidazolium iodide [doim][I], 1-ethyl-3-methylimidazoliumbis(pentafluoroethylsulfonyl)imide [emim][BEI],1,2-dimethyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide[dmpim][BMeI], 3-methyl-1-propylpyridiniumbis(trifluoromethylsulfonyl)imide [pmpy][BMeI],1-ethyl-3-methylimidazolium hexafluorophosphate [emim][PF₆],1-ethyl-3-methylimidazolium bis(trifluoroethylsulfonyl)imide[emim][BMeI], 1-butyl-3-methylpyridiniumbis(trifluoromethylsulfonyl)imide [bmpy][BMeI],1-ethyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[emim][TFES], 1-butyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate [bmim][TFES],1-dodecyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[dmim][TFES], 1-heptyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate [hmim][TFES],1-butyl-3-methylimidazolium acetate [bmim][Ac],1-butyl-3-methylimidazolium2-(1,2,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate[bmim][FS], 1-butyl-3-methylimidazolium1,1,2,3,3,3-hexafluoropropanesulfonate [bmim][HFPS],1-butyl-3-methylimidazolium methyl sulfonate [bmim][MeSO₄],1-butyl-3-methylimidazolium thiocyanate [bmim][SCN],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES],1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES],1-ethyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide[emim][BEI], 1-butyl-3-methylimidazolium1,1,2,3,3-hexafluoropropanesulfonate [bmim][HFPS],tetradecyl(trihexyl)phosphonium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [6,6,6,14-P][TPES],and tributyl(tetradecyl)phosphonium1,1,2,3,3,3-hexafluoropropanesulfonate [4,4,4,14-P][HFPS].

In another embodiment, combinations of refrigerant and lubricant usefulfor vapor compression systems may include difluoromethane (HFC-32) and1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆],difluoromethane (HFC-32) and 1-butyl-3-methylimidazoliumtetrafluoroborate [bmim][BF₄], pentafluoroethane (HFC-125) and1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆],1,1,1,2-tetrafluoroethane (HFC-134a) and 1-butyl-3-methylimidazoliumhexafluorophosphate [bmim][PF₆], 1,1,1-trifluoroethane (HFC-143a) and1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆],1,1-difluoroethane (HFC-152a) and 1-butyl-3-methylimidazoliumhexafluorophosphate [bmim][PF₆], difluoromethane (HFC-32) and1,2-dimethyl-3-propylimidazolium tris(trifluoromethylsulfonyl)methide[dmpim][TMeM], difluoromethane (HFC-32) and 1-octyl-3-methylimidazoliumiodide [omim][I], difluoromethane (HFC-32) and 1,3-dioctylimidazoliumiodide [doim][I], difluoromethane (HFC-32) and1-ethyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide[emim][BEI], difluoromethane (HFC-32) and1,2-dimethyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide[dmpim][BMeI], difluoromethane (HFC-32) and 3-methyl-1-propylpyridiniumbis(trifluoromethylsulfonyl)imide [pmpy][BMeI], trifluoromethane(HFC-23) and 1-butyl-3-methylimidazolium hexafluorophosphate[bmim][PF₆], trifluoromethane (HFC-23) and 1-ethyl-3-methylimidazoliumhexafluorophosphate [emim][PF₆], difluoromethane (HFC-32) and1-ethyl-3-methylimidazolium bis(trifluoroethylsulfonyl)imide[emim][BMeI], difluoromethane (HFC-32) and 1-butyl-3-methylpyridiniumbis(trifluoromethylsulfonyl)imide [bmpy][BMeI], difluoromethane (HFC-32)and 1-ethyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[emim][TFES], difluoromethane (HFC-32) and 1-butyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate [bmim][TFES], difluoromethane(HFC-32) and 1-dodecyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate [dmim][TFES], difluoromethane(HFC-32) and 1-heptyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate [hmim][TFES], difluoromethane(HFC-32) and 1-butyl-3-methylimidazolium acetate [bmim][Ac], (HFC-32)and 1-butyl-3-methylimidazolium2-(1,2,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate[bmim][FS], difluoromethane (HFC-32) and 1-butyl-3-methylimidazolium1,1,2,3,3,3-hexafluoropropanesulfonate [bmim][HFPS], difluoromethane(HFC-32) and 1-butyl-3-methylimidazolium methyl sulfonate [bmim][MeSO₄],difluoromethane (HFC-32) and 1-butyl-3-methylimidazolium thiocyanate[bmim][SCN], difluoromethane (HFC-32) and 1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES],difluoromethane (HFC-32) and 1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES],1,1,1,2-tetrafluoroethane (HFC-134a) and 1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES],1,1,1,2-tetrafluoroethane (HFC-134a) and 1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES],1,1,1,2-tetrafluoroethane (HFC-134a) and 1-ethyl-3-methylimidazoliumbis(pentafluoroethylsulfonyl)imide [emim][BEI],1,1,1,2-tetrafluoroethane (HFC-134a) and 1-butyl-3-methylimidazolium1,1,2,3,3-hexafluoropropanesulfonate [bmim][HFPS],1,1,1,2-tetrafluoroethane (HFC-134a) and tetradecyl(trihexyl)phosphonium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [6,6,6,14-P][TPES],1,1,1,2-tetrafluoroethane (HFC-134a) and tributyl(tetradecyl)phosphonium1,1,2,3,3,3-hexafluoropropanesulfonate [4,4,4,14-P][HFPS], carbondioxide (CO₂) and 1-butyl-3-methylimidazolium hexafluorophosphate[bmim][PF₆], carbon dioxide (CO₂) and 1-butyl-3-methylimidazoliumtetrafluoroborate [bmim][BF₄].

In alternative embodiments of this invention, a refrigerant may be anyone or more of all of the members of the total group of refrigerantsdisclosed herein. In those embodiments, the refrigerant may also,however, be any one or more of those members of a subgroup of the totalgroup of refrigerants disclosed herein, where the subgroup is formed byexcluding any one or more other members from the total group. As aresult, the refrigerant in those embodiments may not only be any one ormore of the refrigerants in any subgroup of any size that may beselected from the total group of refrigerants in all the variousdifferent combinations of individual members of the total group, but themembers in any subgroup may thus be used in the absence of one or moreof the members of the total group that have been excluded to form thesubgroup. The subgroup formed by excluding various members from thetotal group of refrigerants may, moreover, be an individual member ofthe total group such that that refrigerant is used in the absence of allother members of the total group except the selected individual member.

Correspondingly, in further alternative embodiments of this invention,an ionic liquid may be any one or more of all of the members of thetotal group of ionic liquids disclosed herein. In those embodiments, theliquid may also, however, be any one or more of those members of asubgroup of the total group of ionic liquids disclosed herein, where thesubgroup is formed by excluding any one or more other members from thetotal group. As a result, the ionic liquid in those embodiments may notonly be any one or more of the ionic liquids in any subgroup of any sizethat may be selected from the total group of ionic liquids in all thevarious different combinations of individual members of the total group,but the members in any subgroup may thus be used in the absence of oneor more of the members of the total group that have been excluded toform the subgroup. The subgroup formed by excluding various members fromthe total group of ionic liquids may, moreover, be an individual memberof the total group such that that ionic liquid is used in the absence ofall other members of the total group except the selected individualmember.

As a result, in yet other alternative embodiments of this invention,pairings of one or more particular refrigerants and one or moreparticular ionic liquids may be formed from (i) any one or more of allof the members of the total group of refrigerants disclosed herein,selected as described above as a single member or any subgroup of anysize taken from the total group of refrigerants in all the variousdifferent combinations of individual members of that total group,together with (ii) any one or more of all of the members of the totalgroup of ionic liquids disclosed herein, selected as described above asa single member or any subgroup of any size taken from the total groupof ionic liquids in all the various different combinations of individualmembers of that total group.

The following examples are presented to illustrate the advantages of thepresent invention and to assist one of ordinary skill in making andusing the same. These examples are not intended in any way otherwise tolimit the scope of the disclosure or the appended claims. The operationof this invention is illustrated in terms of the extent of solubility ofvarious refrigerants and various ionic liquids in or with each other.

General Methods and Materials

1-Butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF₆],C₈H₁₅N₂F₆P, molecular weight 284 g mol⁻¹), 1-butyl-3-methylimidazoliumtetrafluoroborate ([bmim][BF₄], C₈H₁₅N₂F₄B, molecular weight 226 gmol⁻¹), 1,2-dimethyl-3-propylimidazoliumtris(trifluoromethylsulfonyl)methide ([dmpim][tTFMSmethide],C₁₂H₁₅N₂F₉O₆S₃, molecular weight 550 g mol⁻¹),1,2-dimethyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide([dmpim][bTFMSimide], C₁₀H₁₅N₃F₆O₄S₂, molecular weight 419 g mol⁻¹),1-ethyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide([emim][bPFESimide], C₁₀H₁₁N₃F₁₀O₄S₂, molecular weight 491.33 g mol⁻¹),1-propyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide([pmpy][bTFMSimide], C₁₁H₁₄N₂F₆O₄S₂, molecular weight 416.36 g mol⁻¹),1-ethyl-3-methylimidazolium hexafluorophosphate ([emim][PF₆],C₆H₁₁F₆N₂P, molecular weight 265.13 g mol⁻¹),1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([emim][BMeI], C₈H₁₁F₆N₃O₄S₂, molecular weight 197.98 g mol⁻¹),1-butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide([BMPy][bTFMSimide], C₁₂H₁₆F₆N₂O₄S₂, molecular weight 430.39 g mol⁻¹)were each obtained from Fluka Chemika (may be obtained fromSigma-Aldrich, St. Louis, Mo.) with a purity of >96 to 97% each.Trifluoromethane (HFC-23), difluoromethane (HFC-32, CH₂F₂, molecularweight 52.02 g mol⁻¹), pentafluoroethane (HFC-125, C₂HF₅, molecularweight 120.02 g mol⁻¹), 1,1,1,2-tetrafluoroethane (HFC-134a, C₂H₂F₄,molecular weight 102.03 g mol⁻¹), 1,1,1-trifluoroethane (HFC-143a,C₂H₃F₃, molecular weight 82.04 g mol⁻¹), and 1,1-difluoroethane(HFC-152a, C₂H₄F₂, molecular weight 66.05 g mol⁻¹) were obtained fromDuPont Fluorochemicals (Wilmington, Del.), with a minimum purity of99.99%. A molecular sieve trap was installed to remove trace amounts ofwater from the gases and each of the ionic liquids tested were degassedprior to making solubility measurements.

The following nomenclature and abbreviations are used:

C=concentration (mol·m⁻³)

C_(b)=buoyancy force (N)

C_(f)=correction factor (kg)

C₀=initial concentration (mol·m⁻³)

C_(s)=saturation concentration (mol·m⁻³)

C>=space-averaged concentration (mol·m⁻³)

D=diffusion constant (m²·s⁻¹)

g=gravitational acceleration (9.80665 m·s⁻²)

L=length (m)

m_(a)=mass absorbed (kg)=

m_(i)=mass of i-th species on sample side of balance (kg)

m_(j)=mass of j-th species on counterweight side of balance (kg)

m_(IL)=mass of ionic liquid sample (kg)

MW_(i)=molecular weight of i-th species (kg·mol⁻¹)

N=n-th number component

P=pressure (MPa)

P₀ initial pressure (MPa)

t=time (s)

T_(ci)i=critical temperature of i-th species (K)

T_(i)=temperature of i-th species (K)

T_(j)=temperature of j-th species (K)

T_(s)=temperature of sample (K)

V_(i)=volume of i-th species (m³)

V_(IL)=volume of ionic liquid (m³)

{tilde over (V)}_(m)=liquid sample volume (m³)

{tilde over (V)}_(g)=molar volume of gas (m³·mol⁻¹)

{tilde over (V)}_(i)=molar volume of i-th species (m³·mol¹)

{tilde over (V)}_(IL)=molar volume of ionic liquid (m³·mol⁻¹)

{tilde over (V)}_(m)=molar volume of mixture (m³·mol⁻¹)

{tilde over (V)}₀=initial molar volume (m³·mol⁻¹)

Δ{tilde over (V)}=change in molar volume (m³·mol⁻¹)

x_(i)=mole fraction of i-th species

z=depth (m)

λ_(n)=eigenvalue (m⁻¹)

ρ_(g)=density of gas (kg·m⁻³)

ρ_(i)=density of i-th component on sample side of balance (kg·m⁻³)

ρ_(j)=density of j-th component on counter weight side of balance(kg·m⁻³)

ρ_(air)=density of air (kg·m⁻³)

ρ_(s)=density of sample (kg·m³)

Units

Pa≡Pascal

MPa≡Mega Pascal

mol≡mole

m≡meter

cm≡centimeter

K≡Kelvin

N≡Newton

J≡Joule

kJ≡kilojoule

kg≡kilogram

mg≡milligram

μg≡microgram

T≡temperature

P≡pressure

mbar≡millibar

min≡minute

° C. or C≡degrees Centigrade

° F.≡degrees Fahrenheit

sec≡second

kW≡kilowatt

kg/s≡kilogram/second

In the following description, (A)-(D) provide syntheses for anions ofionic liquids that are useful as lubricants for the invention, and(E)-(W) provide syntheses for ionic liquids useful as lubricants for theinvention.

Preparation of Anions not Generally Available Commercially

(A) Synthesis of potassium 1,1,2,2-tetrafluoroethanesulfonate (TFES-K)([HCF₂CF₂SO₃]⁻)

A 1-gallon Hastelloy® C276 reaction vessel was charged with a solutionof potassium sulfite hydrate (176 g, 1.0 mol), potassium metabisulfite(610 g, 2.8 mol) and deionized water (2000 ml). The pH of this solutionwas 5.8. The vessel was cooled to 18 degrees C., evacuated to 0.10 MPa,and purged with nitrogen. The evacuate/purge cycle was repeated two moretimes. To the vessel was then added tetrafluoroethylene (TFE, 66 g), andit was heated to 100 degrees C. at which time the inside pressure was1.14 MPa. The reaction temperature was increased to 125 degrees C. andkept there for 3 h. As the TFE pressure decreased due to the reaction,more TFE was added in small aliquots (20-30 g each) to maintainoperating pressure roughly between 1.14 and 1.48 MPa. Once 500 g (5.0mol) of TFE had been fed after the initial 66 g precharge, the vesselwas vented and cooled to 25 degrees C. The pH of the clear light yellowreaction solution was 10-11. This solution was buffered to pH 7 throughthe addition of potassium metabisulfite (16 g).

The water was removed in vacuo on a rotary evaporator to produce a wetsolid. The solid was then placed in a freeze dryer (Virtis Freezemobile35xl; Gardiner, N.Y.) for 72 hr to reduce the water content toapproximately 1.5 wt % (1387 g crude material). The theoretical mass oftotal solids was 1351 g. The mass balance was very close to ideal andthe isolated solid had slightly higher mass due to moisture. This addedfreeze drying step had the advantage of producing a free-flowing whitepowder whereas treatment in a vacuum oven resulted in a soapy solid cakethat was very difficult to remove and had to be chipped and broken outof the flask.

The crude TFES-K can be further purified and isolated by extraction withreagent grade acetone, filtration, and drying.

¹⁹F NMR (D₂O)

−122

(dt, J_(FH)=6 Hz, J_(FF)=6 Hz, 2F); −136.1 (dt, J_(FH)=53 Hz, 2F).

¹H NMR (D₂O)

6.4 (tt, J_(FH)=53 Hz, J_(FH)=6 Hz, 1H).

% Water by Karl-Fisher titration: 580 ppm.

Analytical calculation for C₂HO₃F₄SK: C, 10.9; H, 0.5; N,0.0.Experimental results: C, 11.1; H, 0.7; N, 0.2.

Mp (DSC): 242 degrees C.

TGA (air): 10% wt. loss @ 367 degrees C., 50% wt. loss @ 375 degrees C.

TGA (N₂): 10% wt. loss @ 363 degrees C., 50% wt. loss @ 375 degrees C.

(B) Synthesis ofpotassium-1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate (TPES-K)

A 1-gallon Hastelloy® C276 reaction vessel was charged with a solutionof potassium sulfite hydrate (88 g, 0.56 mol), potassium metabisulfite(340 g, 1.53 mol) and deionized water (2000 ml). The vessel was cooledto 7 degrees C., evacuated to 0.05 MPa, and purged with nitrogen. Theevacuate/purge cycle was repeated two more times. To the vessel was thenadded perfluoro(ethylvinyl ether) (PEVE, 600 g, 2.78 mol), and it washeated to 125 degrees C. at which time the inside pressure was 2.31 MPa.The reaction temperature was maintained at 125 degrees C. for 10 hr. Thepressure dropped to 0.26 MPa at which point the vessel was vented andcooled to 25 degrees C. The crude reaction product was a whitecrystalline precipitate with a colorless aqueous layer (pH=7) above it.

The ¹⁹F NMR spectrum of the white solid showed pure desired product,while the spectrum of the aqueous layer showed a small but detectableamount of a fluorinated impurity. The desired isomer is less soluble inwater so it precipitated in isomerically pure form.

The product slurry was suction filtered through a fritted glass funnel,and the wet cake was dried in a vacuum oven (60 degrees C., 0.01 MPa)for 48 hr. The product was obtained as off-white crystals (904 g, 97%yield).

¹⁹F NMR (D₂O) δ −86

(s, 3F); −89.2, −91.3 (subsplit ABq, J_(FF)=147 Hz, 2F); −119.3, −121.2(subsplit ABq, J_(FF)=258 Hz, 2F); −144.3 (dm, J_(FH)=53 Hz, 1F).

¹H NMR (D₂O) δ 6.7 (dm, J_(FH)=53 Hz, 1H).

Mp (DSC) 263 degrees C.

Analytical calculation for C₄HO₄F₈SK: C, 14.3; H, 0.3.Experimentalresults: C, 14.1; H, 0.3.

TGA (air): 10% wt. loss @ 359 degrees C., 50% wt. loss @ 367 degrees C.

TGA (N₂): 10% wt. loss @ 362 degrees C., 50% wt. loss @ 374 degrees C.

(C) Synthesis ofpotassium-1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate (TTES-K)

A 1-gallon Hastelloy® C276 reaction vessel was charged with a solutionof potassium sulfite hydrate (114 g, 0.72 mol), potassium metabisulfite(440 g, 1.98 mol) and deionized water (2000 ml). The pH of this solutionwas 5.8. The vessel was cooled to −35 degrees C., evacuated to 0.08 MPa,and purged with nitrogen. The evacuate/purge cycle was repeated two moretimes. To the vessel was then added perfluoro(methylvinyl ether) (PMVE,600 g, 3.61 mol) and it was heated to 125 degrees C. at which time theinside pressure was 3.29 MPa. The reaction temperature was maintained at125 degrees C. for 6 hr. The pressure dropped to 0.27 MPa at which pointthe vessel was vented and cooled to 25 degrees C. Once cooled, a whitecrystalline precipitate of the desired product formed leaving acolorless clear aqueous solution above it (pH=7).

The ¹⁹F NMR spectrum of the white solid showed pure desired product,while the spectrum of the aqueous layer showed a small but detectableamount of a fluorinated impurity.

The solution was suction filtered through a fritted glass funnel for 6hr to remove most of the water. The wet cake was then dried in a vacuumoven at 0.01 MPa and 50 degrees C. for 48 h. This gave 854 g (83% yield)of a white powder. The final product was isomerically pure (by ¹⁹F and¹H NMR) since the undesired isomer remained in the water duringfiltration.

¹⁹F NMR (D₂O)

−59

(d, J_(FH)=4 Hz, 3F); −119.6, −120.2 (subsplit ABq, J=260 Hz, 2F);−144.9 (dm, J_(FH)=53 Hz, 1F).

¹H NMR (D₂O)

6.6 (dm, J_(FH)=53 Hz, 1H).

% Water by Karl-Fisher titration: 71 ppm.

Analytical calculation for C₃HF₆SO₄K: C, 12.6; H, 0.4; N,0.0.Experimental results: C, 12.6; H, 0.0; N, 0.1.

Mp (DSC) 257 degrees C.

TGA (air): 10% wt. loss @ 343 degrees C., 50% wt. loss @ 358 degrees C.

TGA (N₂): 10% wt. loss @ 341 degrees C., 50% wt. loss @ 357 degrees C.

(D) Synthesis of sodium 1,1,2,3,3,3-hexafluoropropanesulfonate (HFPS—Na)

A 1-gallon Hastelloy® C reaction vessel was charged with a solution ofanhydrous sodium sulfite (25 g, 0.20 mol), sodium bisulfite 73 g, (0.70mol) and of deionized water (400 ml). The pH of this solution was 5.7.The vessel was cooled to 4 degrees C., evacuated to 0.08 MPa, and thencharged with hexafluoropropene (HFP, 120 g, 0.8 mol, 0.43 MPa). Thevessel was heated with agitation to 120 degrees C. and kept there for 3hr. The pressure rose to a maximum of 1.83 MPa and then dropped down to0.27 MPa within 30 minutes. At the end, the vessel was cooled and theremaining HFP was vented, and the reactor was purged with nitrogen. Thefinal solution had a pH of 7.3.

The water was removed in vacuo on a rotary evaporator to produce a wetsolid. The solid was then placed in a vacuum oven (0.02 MPa, 140 degreesC., 48 hr) to produce 219 g of white solid, which containedapproximately 1 wt % water. The theoretical mass of total solids was 217g.

The crude HFPS—Na can be further purified and isolated by extractionwith reagent grade acetone, filtration, and drying.

¹⁹F NMR (D₂O)

−74

(m, 3F); −113.1, −120.4 (ABq, J=264 Hz, 2F); −211.6 (dm, 1F).

¹H NMR (D₂O)

5.8 (dm, J_(FH)=43 Hz, 1H).

Mp (DSC) 126 degrees C.

TGA (air): 10% wt. loss @ 326 degrees C., 50% wt. loss @ 446 degrees C.

TGA (N₂): 10% wt. loss @ 322 degrees C., 50% wt. loss @ 449 degrees C.

Preparation of Ionic Liquids

E) Synthesis of 1-butyl-2,3-dimethylimidazolium1,1,2,2-tetrafluoroethanesulfonate

1-Butyl-2,3-dimethylimidazolium chloride (22.8 g, 0.121 moles) was mixedwith reagent-grade acetone (250 ml) in a large round-bottomed flask andstirred vigorously. Potassium 1,1,2,2-tetrafluoroethanesulfonate(TFES-K, 26.6 g, 0.121 moles), was added to reagent grade acetone (250ml) in a separate round-bottomed flask, and this solution was carefullyadded to the 1-butyl-2,3-dimethylimidazolium chloride solution. Thelarge flask was lowered into an oil bath and heated at 60 degrees C.under reflux for 10 hours. The reaction mixture was then filtered usinga large frit glass funnel to remove the white KCl precipitate formed,and the filtrate was placed on a rotary evaporator for 4 hours to removethe acetone.

The reaction scheme is shown below:

F) Synthesis of 1-butyl-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate

1-Butyl-3-methylimidazolium chloride (60.0 g) and high purity dryacetone (>99.5%, Aldrich, 300 ml) were combined in a 11 flask and warmedto reflux with magnetic stirring until the solid completely dissolved.At room temperature in a separate 11 flask,potassium-1,1,2,2-tetrafluoroethanesulfonte (TFES-K, 75.6 g) wasdissolved in high purity dry acetone (500 ml). These two solutions werecombined at room temperature and allowed to stir magnetically for 2 hrunder positive nitrogen pressure. The stirring was stopped and the KClprecipitate was allowed to settle, then removed by suction filtrationthrough a fritted glass funnel with a celite pad. The acetone wasremoved in vacuo to give a yellow oil. The oil was further purified bydiluting with high purity acetone (100 ml) and stirring withdecolorizing carbon (5 g). The mixture was again suction filtered andthe acetone removed in vacuo to give a colorless oil. This was furtherdried at 4 Pa and 25 degrees C. for 6 hr to provide 83.6 g of product.

¹⁹F NMR (DMSO-d₆)

−124

(dt, J=6 Hz, J=8 Hz, 2F); −136.8 (dt, J=53 Hz, 2F).

¹H NMR (DMSO-d₆) δ 0.9 (t, J=7.4 Hz, 3H); 1.3 (m, 2H); 1.8 (m, 2H); 3.9(s, 3H); 4.2 (t, J=7 Hz, 2H); 6.3 (dt, J=53 Hz, J=6 Hz, 1H); 7.4 (s,1H); 7.5 (s, 1H); 8.7 (s, 1H).

% Water by Karl-Fisher titration: 0.14%.

Analytical calculation for C₉H₁₂F₆N₂O₃S: C, 37.6; H, 4.7; N, 8.8.Experimental Results: C, 37.6; H, 4.6; N, 8.7.

TGA (air): 10% wt. loss @ 380 degrees C., 50% wt. loss @ 420 degrees C.

TGA (N₂): 10% wt. loss @ 375 degrees C., 50% wt. loss @ 422 degrees C.

G) Synthesis of 1-ethyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate

To a 500 ml round bottom flask was added 1-ethyl-3methylimidazoliumchloride (Emim-Cl, 98%, 61.0 g) and reagent grade acetone (500 ml). Themixture was gently warmed (50 degrees C.) until almost all of theEmim-Cl dissolved. To a separate 500 ml flask was added potassium1,1,2,2-tetrafluoroethanesulfonate (TFES-K, 90.2 g) along with reagentgrade acetone (350 ml). This second mixture was stirred magnetically at24 degrees C. until all of the TFES-K dissolved.

These solutions were combined in a 11 flask producing a milky whitesuspension. The mixture was stirred at 24 degrees C. for 24 hrs. The KClprecipitate was then allowed to settle leaving a clear green solutionabove it.

The reaction mixture was filtered once through a celite/acetone pad andagain through a fritted glass funnel to remove the KCl. The acetone wasremoved in vacuo first on a rotovap and then on a high vacuum line (4Pa, 25 degrees C.) 25 for 2 hr. The product was a viscous light yellowoil (76.0 g, 64% yield).

The reaction scheme is shown below:

¹⁹F NMR (DMSO-d₆)

−124

(dt, J_(FH)=6 Hz, J_(FF)=6 Hz, 2F); −138.4 (dt, J_(FH)=53 Hz, 2F).

¹H NMR (DMSO-d₆)

1.3 (t, J=7.3 Hz, 3H); 3.7 (s, 3H); 4.0 (q, J=7.3 Hz, 2H);

6.1 (tt, J_(FH)=53 Hz, J_(FH)=6 Hz, 1H); 7.2 (s, 1H); 7.3 (s, 1H); 8.5(s, 1H).

% Water by Karl-Fisher titration: 0.18%.

Analytical calculation for C₈H₁₂N₂O₃F₄S: C, 32.9; H, 4.1; N, 9.6.Found:C, 33.3; H, 3.7; N, 9.6.

Mp 45-46 degrees C.

TGA (air): 10% wt. loss @ 379 degrees C., 50% wt. loss @ 420 degrees C.

TGA (N₂): 10% wt. loss @ 378 degrees C., 50% wt. loss @ 418 degrees C.

H) Synthesis of 1-ethyl-3-methylimidazolium1,1,2,3,3,3-hexafluoropropanesulfonate

To a 11 round bottom flask was added 1-ethyl-3-methylimidazoliumchloride (Emim-Cl, 98%, 50.5 g) and reagent grade acetone (400 ml). Themixture was gently warmed (50 degrees C.) until almost all of theEmim-Cl dissolved. To a separate 500 ml flask was added potassium1,1,2,3,3,3-hexafluoropropanesulfonate (HFPS—K, 92.2 g) along withreagent grade acetone (300 ml). This second mixture was stirredmagnetically at room temperature until all of the HFPS—K dissolved.

These solutions were combined and stirred under positive N₂ pressure at26 degrees C. for 12 hr producing a milky white suspension. The KClprecipitate was allowed to settle overnight leaving a clear yellowsolution above it.

The reaction mixture was filtered once through a celite/acetone pad andagain through a fritted glass funnel. The acetone was removed in vacuofirst on a rotovap and then on a high vacuum line (4 Pa, 25 degrees C.)for 2 hr. The product was a viscious light yellow oil (103.8 g, 89%yield).

The reaction scheme is shown below:

¹⁹F NMR (DMSO-d₆) δ −73.8 (s, 3F); −114.5, −121.0 (ABq, J=258 Hz, 2F);−210.6 (m, 1F, J_(HF)=41.5 Hz).

¹H NMR (DMSO-d₆)

1.4 (t, J=7.3 Hz, 3H); 3.9 (s, 3H); 4.2 (q, J=7.3 Hz, 2H,);

5.8 (m, J_(HF)=41.5 Hz, 1H,); 7.7 (s, 1H); 7.8 (s, 1H); 9.1 (s, 1H).

% Water by Karl-Fisher titration: 0.12%.

Analytical calculation for C₉H₁₂N₂O₃F₆S: C, 31.5; H, 3.5; N, 8.2.Experimental Results: C, 30.9; H, 3.3; N, 7.8.

TGA (air): 10% wt. loss @ 342 degrees C., 50% wt. loss @ 373 degrees C.

TGA (N₂): 10% wt. loss @ 341 degrees C., 50% wt. loss @ 374 degrees C.

I) Synthesis of 1-hexyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate

1-Hexyl-3-methylimidazolium chloride (10 g, 0.0493 moles) was mixed withreagent-grade acetone (100 ml) in a large round-bottomed flask andstirred vigorously under a nitrogen blanket. Potassium1,1,2,2-tetrafluoroethane sulfonate (TFES-K, 10 g, 0.0455 moles) wasadded to reagent grade acetone (100 ml) in a separate round-bottomedflask, and this solution was carefully added to the1-hexyl-3-methylimidazolium chloride/acetone mixture. The mixture wasleft to stir overnight. The reaction mixture was then filtered using alarge frit glass funnel to remove the white KCl precipitate formed, andthe filtrate was placed on a rotary evaporator for 4 hours to remove theacetone.The reaction scheme is shown below:

J) Synthesis of 1-dodecyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate

1-Dodecyl-3-methylimidazolium chloride (34.16 g, 0.119 moles) waspartially dissolved in reagent-grade acetone (400 ml) in a largeround-bottomed flask and stirred vigorously. Potassium1,1,2,2-tetrafluoroethanesulfonate (TFES-K, 26.24 g, 0.119 moles) wasadded to reagent grade acetone (400 ml) in a separate round-bottomedflask, and this solution was carefully added to the1-dodecyl-3-methylimidazolium chloride solution. The reaction mixturewas heated at 60 degrees C. under reflux for approximately 16 hours. Thereaction mixture was then filtered using a large frit glass funnel toremove the white KCl precipitate formed, and the filtrate was placed ona rotary evaporator for 4 hours to remove the acetone.The reaction scheme is shown below:

K) Synthesis of 1-hexadecyl-3-methylimidazolium1,1,2,2-tetrafluoroethanesulfonate

1-Hexadecyl-3-methylimidazolium chloride (17.0 g, 0.0496 moles) waspartially dissolved in reagent-grade acetone (100 ml) in a largeround-bottomed flask and stirred vigorously. Potassium1,1,2,2-tetrafluoroethanesulfonate (TFES-K, 10.9 g, 0.0495 moles) wasadded to reagent grade acetone (100 ml) in a separate round-bottomedflask, and this solution was carefully added to the1-hexadecyl-3-methylimidazolium chloride solution. The reaction mixturewas heated at 60 degrees C. under reflux for approximately 16 hours. Thereaction mixture was then filtered using a large frit glass funnel toremove the white KCl precipitate formed, and the filtrate was placed ona rotary evaporator for 4 hours to remove the acetone.The reaction scheme is shown below:

L) Synthesis of 1-octadecyl-3-methylimidazolium1,1,2,2-tetrafluoroethaneulfonate

1-Octadecyl-3-methylimidazolium chloride (17.0 g, 0.0458 moles) waspartially dissolved in reagent-grade acetone (200 ml) in a largeround-bottomed flask and stirred vigorously. Potassium1,1,2,2-tetrafluoroethanesulfonate (TFES-K, 10.1 g, 0.0459 moles), wasadded to reagent grade acetone (200 ml) in a separate round-bottomedflask, and this solution was carefully added to the1-octadecyl-3-methylimidazolium chloride solution. The reaction mixturewas heated at 60 degrees C. under reflux for approximately 16 hours. Thereaction mixture was then filtered using a large frit glass funnel toremove the white KCl precipitate formed, and the filtrate was placed ona rotary evaporator for 4 hours to remove the acetone.The reaction scheme is shown below:

M) Synthesis of 1-propyl-3-(1,1,2,2-TFES) imidazolium1,1,2,2-tetrafluoroethanesulfonate

Imidazole (19.2 g) was added to of tetrahydrofuran (80 mls). A glassshaker tube reaction vessel was filled with the THF-containing imidazolesolution. The vessel was cooled to 18° C., evacuated to 0.08 MPa, andpurged with nitrogen. The evacuate/purge cycle was repeated two moretimes. Tetrafluoroethylene (TFE, 5 g) was then added to the vessel, andit was heated to 100 degrees C., at which time the inside pressure wasabout 0.72 MPa. As the TFE pressure decreased due to the reaction, moreTFE was added in small aliquots (5 g each) to maintain operatingpressure roughly between 0.34 MPa and 0.86 MPa. Once 40 g of TFE hadbeen fed, the vessel was vented and cooled to 25 degrees C. The THF wasthen removed under vacuum and the product was vacuum distilled at 40degrees C. to yield pure product as shown by ¹H and ¹⁹F NMR (yield 44g). Iodopropane (16.99 g) was mixed with1-(1,1,2,2-tetrafluoroethyl)imidazole (16.8 g) in dry acetonitrile (100ml), and the mixture was refluxed for 3 days. The solvent was removed invacuo, yielding a yellow waxy solid (yield 29 g). The product,1-propyl-3-(1,1,2,2-tetrafluoroethyl)imidazolium iodide was confirmed by¹H NMR (in CD₃CN) [0.96 (t, 3H); 1.99 (m, 2H); 4.27 (t, 2H); 6.75 (t,1H); 7.72 (d, 2H); 9.95 (s, 1H)].

Iodide (24 g) was then added to 60 ml of dry acetone, followed by 15.4 gof potassium 1,1,2,2-tetrafluoroethanesulfonate in 75 ml of dry acetone.The mixture was heated at 60 degrees C. overnight and a dense whiteprecipitate was formed (potassium iodide). The mixture was cooled,filtered, and the solvent from the filtrate was removed using a rotaryevaporator. Some further potassium iodide was removed under filtration.The product was further purified by adding 50 g of acetone, 1 g ofcharcoal, 1 g of celite and 1 g of silica gel. The mixture was stirredfor 2 hours, filtered and the solvent removed. This yielded 15 g of aliquid, shown by NMR to be the desired product.

N) Synthesis of 1-butyl-3-methylimidazolium1,1,2,3,3,3-hexafluoropropanesulfonate (Bmim-HFPS)

1-Butyl-3-methylimidazolium chloride (Bmim-Cl, 50.0 g) and high puritydry acetone (>99.5%, 500 ml) were combined in a 11 flask and warmed toreflux with magnetic stirring until the solid all dissolved. At roomtemperature in a separate 11 flask,potassium-1,1,2,3,3,3-hexafluoropropanesulfonte (HFPS—K) was dissolvedin high purity dry acetone (550 ml). These two solutions were combinedat room temperature and allowed to stir magnetically for 12 hr underpositive nitrogen pressure. The stirring was stopped, and the KClprecipitate was allowed to settle. This solid was removed by suctionfiltration through a fritted glass funnel with a celite pad. The acetonewas removed in vacuo to give a yellow oil. The oil was further purifiedby diluting with high purity acetone (100 ml) and stirring withdecolorizing carbon (5 g). The mixture was suction filtered and theacetone removed in vacuo to give a colorless oil. This was further driedat 4 Pa and 25 degrees C. for 2 hr to provide 68.6 g of product.

¹⁹F NMR (DMSO-d₆) δ −73

(s, 3F); −114.5, −121.0 (ABq, J=258 Hz, 2F); −210.6 (m, J=42 Hz, 1F).

¹H NMR (DMSO-d₆) δ 0.9 (t, J=7.4 Hz, 3H); 1.3 (m, 2H); 1.8 (m, 2H); 3.9(s, 3H); 4.2 (t, J=7 Hz, 2H); 5.8 (dm, J=42 Hz, 1H); 7.7 (s, 1H); 7.8(s, 1H); 9.1 (s, 1H).

% Water by Karl-Fisher titration: 0.12%.

Analytical calculation for C₉H₁₂F₆N₂O₃S: C, 35.7; H, 4.4; N, 7.6.Experimental Results: C, 34.7; H, 3.8; N, 7.2.

TGA (air): 10% wt. loss @ 340 degrees C., 50% wt. loss @ 367 degrees C.

TGA (N₂): 10% wt. loss @ 335 degrees C., 50% wt. loss @ 361 degrees C.

Extractable chloride by ion chromatography: 27 ppm.

O) Synthesis of 1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate (Bmim-TTES)

1-Butyl-3-methylimidazolium chloride (Bmim-Cl, 10.0 g) and deionizedwater (15 ml) were combined at room temperature in a 200 ml flask. Atroom temperature in a separate 200 ml flask, potassium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate (TTES-K, 16.4 g) wasdissolved in deionized water (90 ml). These two solutions were combinedat room temperature and allowed to stir magnetically for 30 min. underpositive nitrogen pressure to give a biphasic mixture with the desiredionic liquid as the bottom phase. The layers were separated, and theaqueous phase was extracted with 2×50 ml portions of methylene chloride.The combined organic layers were dried over magnesium sulfate andconcentrated in vacuo. The colorless oil product was dried at for 4 hrat 5 Pa and 25 degrees C. to afford 15.0 g of product.

¹⁹F NMR (DMSO-d₆) δ −56.8 (d, J_(FH)=4 Hz, 3F); −1 19.5, −119.9(subsplit ABq, J=260 Hz, 2F); −142.2 (dm, J_(FH)=53 Hz, 1F).

¹H NMR (DMSO-d₆) δ 0.9 (t, J=7.4 Hz, 3H); 1.3 (m, 2H); 1.8 (m, 2H); 3.9(s, 3H); 4.2 (t, J=7.0 Hz, 2H); 6.5 (dt, J=53 Hz, J=7 Hz, 1H); 7.7 (s,1H); 7.8 (s, 1H); 9.1 (s, 1H).

% Water by Karl-Fisher titration: 613 ppm.

Analytical calculation for C11H16F6N2O4S: C, 34.2; H, 4.2; N, 7.3.Experimental Results: C, 34.0; H, 4.0; N, 7.1.

TGA (air): 10% wt. loss @ 328 degrees C., 50% wt. loss @ 354 degrees C.

TGA (N₂): 10% wt. loss @ 324 degrees C., 50% wt. loss @ 351 degrees C.

Extractable chloride by ion chromatography: <2 ppm.

P) Synthesis of 1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate (Bmim-TPES)

1-Butyl-3-methylimidazolium chloride (Bmim-Cl, 7.8 g) and dry acetone(150 ml) were combined at room temperature in a 500 ml flask. At roomtemperature in a separate 200 ml flask, potassium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate (TPES-K, 15.0 g) wasdissolved in dry acetone (300 ml). These two solutions were combined andallowed to stir magnetically for 12 hr under positive nitrogen pressure.The KCl precipitate was then allowed to settle leaving a colorlesssolution above it. The reaction mixture was filtered once through acelite/acetone pad and again through a fritted glass funnel to removethe KCl. The acetone was removed in vacuo first on a rotovap and then ona high vacuum line (4 Pa, 25 degrees C.) for 2 hr. Residual KCl wasstill precipitating out of the solution, so methylene chloride (50 ml)was added to the crude product, which was then washed with deionizedwater (2×50 ml). The solution was dried over magnesium sulfate, and thesolvent was removed in vacuo to give the product as a viscous lightyellow oil (12.0 g, 62% yield).

¹⁹F NMR (CD₃CN) δ −85.8 (s, 3F); −87.9, −90.1 (subsplit ABq, J_(FF)=147Hz, 2F); −120.6, −122.4 (subsplit ABq, J_(FF)=258 Hz, 2F); −142.2 (dm,J_(FH)=53 Hz, 1F).

¹H NMR (CD₃CN) δ 1

(t, J=7.4 Hz, 3H); 1.4 (m, 2H); 1.8 (m, 2H); 3.9 (s, 3H);

4.2 (t, J=7.0 Hz, 2H); 6.5 (dm, J=53 Hz, 1H); 7.4 (s, 1H); 7.5 (s, 1H);

8.6 (s, 1H).

% Water by Karl-Fisher titration: 0.461.

Analytical calculation for C12H16F8N2O4S: C, 33.0; H, 3.7. ExperimentalResults: C, 32.0; H, 3.6.

TGA (air): 10% wt. loss @ 334 degrees C., 50% wt. loss @ 353 degrees C.

TGA (N₂): 10% wt. loss @ 330 degrees C., 50% wt. loss @ 365 degrees C.

Q) Synthesis of tetradecyl(tri-n-butyl)phosphonium1,1,2,3,3,3-hexafluoropropanesulfonate ([4.4.4.14]P—HFPS)

To a 41 round bottomed flask was added the ionic liquidtetradecyl(tri-n-butyl)phosphonium chloride (Cyphos® IL 167, 345 g) anddeionized water (1000 ml). The mixture was magnetically stirred until itwas one phase. In a separate 21 flask, potassium1,1,2,3,3,3-hexafluoropropanesulfonate (HFPS—K, 214.2 g) was dissolvedin deionized water (1100 ml). These solutions were combined and stirredunder positive N₂ pressure at 26 degrees C. for 1 hr producing a milkywhite oil. The oil slowly solidified (439 g) and was removed by suctionfiltration and then dissolved in chloroform (300 ml). The remainingaqueous layer (pH=2) was extracted once with chloroform (100 ml). Thechloroform layers were combined and washed with an aqueous sodiumcarbonate solution (50 ml) to remove any acidic impurity. They were thendried over magnesium sulfate, suction filtered, and reduced in vacuofirst on a rotovap and then on a high vacuum line (4 Pa, 100 degrees C.)for 16 hr to yield the final product as a white solid (380 g, 76%yield).

¹⁹F NMR (DMSO-d₆) δ −73

(s, 3F); −114.6, −120.9 (ABq, J=258 Hz, 2F); −210.5 (m, J_(HF)=41.5 Hz,1F).

¹H NMR (DMSO-d₆) δ 0.8 (t, J=7.0 Hz, 3H); 0.9 (t, J=7.0 Hz, 9H); 1.3 (brs, 20H); 1.4 (m, 16H); 2.2 (m, 8H); 5.9 (m, J_(HF)=42 Hz, 1H).

% Water by Karl-Fisher titration: 895 ppm.

Analytical calculation for C29H57F6O3PS: C, 55.2; H, 9.1; N, 0.0.Experimental Results: C, 55.1; H, 8.8; N, 0.0.

TGA (air): 10% wt. loss @ 373 degrees C., 50% wt. loss @ 421 degrees C.

TGA (N₂): 10% wt. loss @ 383 degrees C., 50% wt. loss @ 436 degrees C.

R) Synthesis of tetradecyl(tri-n-hexyl)phosphonium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate ([6.6.6.14]P-TPES)

To a 500 ml round bottomed flask was added acetone (Spectroscopic grade,50 ml) and ionic liquid tetradecyl(tri-n-hexyl)phosphonium chloride(Cyphos® IL 101, 33.7 g). The mixture was magnetically stirred until itwas one phase. In a separate 11 flask, potassium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate (TPES-K, 21.6 g) wasdissolved in acetone (400 ml). These solutions were combined and stirredunder positive N₂ pressure at 26 degrees C. for 12 hr producing a whiteprecipitate of KCl. The precipitate was removed by suction filtration,and the acetone was removed in vacuo on a rotovap to produce the crudeproduct as a cloudy oil (48 g). Chloroform (100 ml) was added, and thesolution was washed once with deionized water (50 ml). It was then driedover magnesium sulfate and reduced in vacuo first on a rotovap and thenon a high vacuum line (8 Pa, 24 degrees C.) for 8 hr to yield the finalproduct as a slightly yellow oil (28 g, 56% yield).

¹⁹F NMR (DMSO-d₆) δ −86.1 (s, 3F); −88.4, −90.3 (subsplit ABq,J_(FF)=147 Hz, 2F); −121.4, −122.4 (subsplit ABq, J_(FF)=258 Hz, 2F);−143.0 (dm, J_(FH)=53 Hz, 1F).

¹H NMR (DMSO-d₆) δ 0.9 (m, 12H); 1.2 (m, 16H); 1.3 (m, 16H); 1.4 (m,8H); 1.5 (m, 8H); 2.2 (m, 8H); 6.3 (dm, J_(FH)=54 Hz, 1H).

% Water by Karl-Fisher titration: 0.11.

Analytical calculation for C36H69F8O4PS: C, 55.4; H, 8.9; N, 0.0.Experimental Results: C, 55.2; H, 8.2; N, 0.1.

TGA (air): 10% wt. loss @ 311 degrees C., 50% wt. loss @ 339 degrees C.

TGA (N₂): 10% wt. loss @ 315 degrees C., 50% wt. loss @ 343 degrees C.

S) Synthesis of tetradecyl(tri-n-hexyl)phosphonium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate ([6.6.6.14]P-TTES)

To a 100 ml round bottomed flask was added acetone (Spectroscopic grade,50 ml) and ionic liquid tetradecyl(tri-n-hexyl)phosphonium chloride(Cyphos® IL 101, 20.2 g). The mixture was magnetically stirred until itwas one phase. In a separate 100 ml flask, potassium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate (TTES-K, 11.2 g) wasdissolved in acetone (100 ml). These solutions were combined and stirredunder positive N₂ pressure at 26 degrees C. for 12 hr producing a whiteprecipitate of KCl.

The precipitate was removed by suction filtration, and the acetone wasremoved in vacuo on a rotovap to produce the crude product as a cloudyoil. The product was diluted with ethyl ether (100 ml) and then washedonce with deionized water (50 ml), twice with an aqueous sodiumcarbonate solution (50 ml) to remove any acidic impurity, and twice morewith deionized water (50 ml). The ether solution was then dried overmagnesium sulfate and reduced in vacuo first on a rotovap and then on ahigh vacuum line (4 Pa, 24 degrees C.) for 8 hr to yield the finalproduct as an oil (19.0 g, 69% yield).

¹⁹F NMR (CD₂Cl₂) δ −60

(d, J_(FH)=4 Hz, 3F); −120.8, −125.1 (subsplit ABq, J=260 Hz, 2F);−143.7 (dm, J_(FH)=53 Hz, 1F).

¹H NMR (CD₂Cl₂) δ 0.9 (m, 12H); 1.2 (m, 16H); 1.3 (m, 16H); 1.4 (m, 8H);1.5 (m, 8H); 2.2 (m, 8H); 6.3 (dm, J_(FH)=54 Hz, 1H).

% Water by Karl-Fisher titration: 412 ppm.

Analytical calculation for C35H69F6O4PS: C, 57.5; H, 9.5; N, 0.0.Experimental results: C, 57.8; H, 9.3; N, 0.0.

TGA (air): 10% wt. loss @ 331 degrees C., 50% wt. loss @ 359 degrees C.

TGA (N₂): 10% wt. loss @ 328 degrees C., 50% wt. loss @ 360 degrees C.

T) Synthesis of 1-ethyl-3-methylimidazolium1,1,2,2-tetrafluoro-2-(pentafluoroethoxy)sulfonate (Emim-TPENTAS)

To a 500 ml round bottomed flask was added 1-ethyl-3-methylimidazoliumchloride (Emim-Cl, 98%, 18.0 g) and reagent grade acetone (150 ml). Themixture was gently warmed (50 degrees C.) until all of the Emim-Cldissolved. In a separate 500 ml flask, potassium1,1,2,2-tetrafluoro-2-(pentafluoroethoxy)sulfonate (TPENTAS-K, 43.7 g)was dissolved in reagent grade acetone (450 ml).

These solutions were combined in a 11 flask producing a whiteprecipitate (KCl). The mixture was stirred at 24 degrees C. for 8 hr.The KCl precipitate was then allowed to settle leaving a clear yellowsolution above it. The KCl was removed by filtration through acelite/acetone pad. The acetone was removed in vacuo to give a yellowoil, which was then diluted with chloroform (100 ml). The chloroform waswashed three times with deionized water (50 ml), dried over magnesiumsulfate, filtered, and reduced in vacuo first on a rotovap and then on ahigh vacuum line (4 Pa, 25 degrees C.) for 8 hr. The product was a lightyellow oil (22.5 g).

¹⁹F NMR (DMSO-d₆) δ −82

(m, 2F); −87.3 (s, 3F); −89.0 (m, 2F); −118.9 (s, 2F).

¹H NMR (DMSO-d₆)

1.5 (t, J=7.3 Hz, 3H); 3.9 (s, 3H); 4.2 (q, J=7.3 Hz, 2H);

7.7 (s, 1H); 7.8 (s, 1H); 9.1 (s, 1H).

% Water by Karl-Fisher titration: 0.17%.

Analytical calculation for C10H11N2O4F9S: C, 28.2; H, 2.6; N, 6.6.Experimental results: C, 28.1; H, 2.9; N, 6.6.

TGA (air): 10% wt. loss @ 351 degrees C., 50% wt. loss @ 401 degrees C.

TGA (N₂): 10% wt. loss @ 349 degrees C., 50% wt. loss @ 406 degrees C.

U) Synthesis of tetrabutylphosphonium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate (TBP-TPES)

To a 200 ml round bottomed flask was added deionized water (100 ml) andtetra-n-butylphosphonium bromide (Cytec Canada Inc., 20.2 g). Themixture was magnetically stirred until the solid all dissolved. In aseparate 300 ml flask, potassium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate (TPES-K, 20.0 g) wasdissolved in deionized water (400 ml) heated to 70 degrees C. Thesesolutions were combined and stirred under positive N₂ pressure at 26degrees C. for 2 hr producing a lower oily layer. The product oil layerwas separated and diluted with chloroform (30 ml), then washed once withan aqueous sodium carbonate solution (4 ml) to remove any acidicimpurity, and three times with deionized water (20 ml). It was thendried over magnesium sulfate and reduced in vacuo first on a rotovap andthen on a high vacuum line (8 Pa, 24 degrees C.) for 2 hr to yield thefinal product as a colorless oil (28.1 g, 85% yield).

¹⁹F NMR (CD₂Cl₂) δ −86.4 (s, 3F); −89.0, −90.8 (subsplit ABq, J_(FF)=147Hz, 2F); −119.2, −125.8 (subsplit ABq, J_(FF)=254 Hz, 2F); −141.7 (dm,J_(FH)=53 Hz, 1F).

¹H NMR (CD₂Cl₂) δ 1.0 (t, J=7.3 Hz, 12H); 1.5 (m, 16H); 2.2 (m, 8H); 6.3(dm, J_(FH)=54 Hz, 1H).

% Water by Karl-Fisher titration: 0.29.

Analytical calculation for C20H37F8O4PS: C, 43.2; H, 6.7; N, 0.0.Experimental results: C, 42.0; H, 6.9; N, 0.1.

Extractable bromide by ion chromatography: 21 ppm.

(V) Preparation of 1,3-dioctylimidazolium iodide [doim][I]

1,3-Dioctylimidazolium iodide [ooim][I] was prepared as described by L.Xu, et al., Journal of Organometallic Chemistry, 2000, 598, 409-416:

Imidazole (2.72 g; 0.04 mmol) and octyl bromide (3.1 g; 0.016 mmol) weredissolved in 55 ml of ethyl acetate. The mixture was refluxed under anitrogen blanket. Initially, the solution was clear and colorless,however upon refluxing approximately 1 hour the mixture became cloudywith a tannish color. The mixture was allowed to reflux overnight. Themixture was then cooled to room temperature (RT) upon which a whiteprecipitate formed. The mixture was extracted with water (2×:30 ml).After drying the solvent with magnesium sulfate, the solvent was removedusing a vacuum, yielding a tannish oil. To the oily residue was added 60ml of toluene followed by 1-iodoctane (4.8 g; 0.02). The mixture wasrefluxed overnight under a nitrogen blanket, resulting in a dark yellowmixture. The yellow oil was collected via a separation funnel rinsedwith toluene (2×:20 ml) and dried under vacuum.

(W) Preparation of 1-methyl-3-octylimidazolium iodide [omim][I]

1-Methyl-3-octylimidazolium iodide [omim][I] was prepared as describedby L. Xu, et al. (Journal of Organometallic Chemistry, 2000, 598,409-416):

1-Methylimidazole (1.65 g; 0.02 mmol) and 1-iodoctane (5.31 g; 0.022mmol) were dissolved in 30 ml of toluene. The reaction was refluxed,whereupon the mixture immediately became yellow in color and cloudy. Themixture was refluxed overnight, during which a yellowish oilyprecipitate formed. The yellowish oil was collected and dried undervacuum.

Gravimetric Microbalance

The gas solubility and diffusivity measurements were made using agravimetric microbalance (Hiden Isochema Ltd, IGA 003, Warrington, UK).The IGA design integrates precise computer-control and measurement ofweight change, pressure and temperature to enable fully automatic andreproducible determination of gas adsorption-desorption isotherms andisobars. The microbalance consists of an electrobalance with sample andcounterweight components inside a stainless steel pressure-vessel asshown in FIG. 18 and described in Example 38, Table 31. The balance hasa weigh range of 0-100 mg with a resolution of 0.1 μg. An enhancedpressure stainless steel (SS316LN) reactor capable of operation to 20.0bar and 100° C. was installed. Approximately 60 mg of ionic liquidsample was added to the sample container and the reactor was sealed. Thesample was dried and degassed by first pulling a course vacuum on thesample with a diaphragm pump (Pfeiffer, model MVP055-3, Asslar, Germany)and then fully evacuating the reactor to 10⁻⁸ bar with a turbopump(Pfeiffer, model TSH-071). While under deep vacuum, the sample washeated to 75° C. for 10 hr with an external water jacket connected to aremote-controlled constant-temperature bath (Huber Ministat, modelcc-S3, Offenburg, Germany). A 30 percent ethylene glycol and 70 percentwater mixture by volume was used as the recirculating fluid with atemperature range of 5 to 90° C. The sample mass slowly decreased asresidual water and gases were removed. Once the mass had stabilized forat least 60 min, the sample dry mass was recorded. The percent weightloss for the various ionic liquids tested was in the range of 1 to 3%.

The IGA003 can operate in both dynamic and static mode. Dynamic modeoperation provides a continuous flow of gas (max. 500 cm³ min⁻¹) pastthe sample and the exhaust valve controls the set-point pressure. Staticmode operation introduces gas into the top of the balance away from thesample and both the admittance and exhaust valves control the set-pointpressure. All absorption measurements were performed in static mode. Thesample temperature was measured with a type K thermocouple with anaccuracy of ±0.1° C. The thermocouple was located inside the reactornext to the sample container. The water jacket maintained the set-pointtemperature automatically to within a typical regulation accuracy of±0.1° C. Four isotherms (at 10, 25, 50, and 75° C.) were measuredbeginning with 10° C. Once the desired temperature was achieved andstable, the admittance and exhaust valves automatically opened andclosed to adjust the pressure to the first set-point. Pressures from10⁻⁹ to 10⁻¹ bar were measured using a capacitance manometer (Pfeiffer,model PKR251), and pressures from 10⁻¹ to 20.0 bar were measured using apiezo-resistive strain gauge (Druck, model PDCR4010, New Fairfield,Conn.). Regulation maintained the reactor pressure set-point to within±4 to 8 mbar. The pressure ramp rate was set at 200 mbar min⁻¹ and thetemperature ramp rate was set at 1° C. min⁻¹. The upper pressure limitof the stainless steel reactor was 20.0 bar, and several isobars up to10 bar (i.e., 0.1, 0.5, 1, 4, 7, 10 bar) were measured. To ensuresufficient time for gas-liquid equilibrium, the ionic liquid sampleswere maintained at set-point for a minimum of 3 hr with a maximumtime-out of 8 hr.

The IGA method exploits the relaxation behavior following pressure andtemperature changes to simultaneously evaluate the time-dependentabsorption and asymptotic uptake. The real-time processor was used todetermine the end-point for each isotherm. The percent relaxation usedas an end point for the real-time analysis was 99 percent. The minimumweight change for real-time analysis was set at 1 μg, the acceptableaverage deviation of the model from the acquired data was set at 7 μg,and the target interval for weight acquisition was set at a typicalvalue of 1 μg. The temperature variation during an isotherm wasmaintained less than 0.1° C. min⁻¹.

Safety features of the IGA003 included a pressure relief valve andover-temperature control for the reactor. The factory-installed reliefvalve was replaced with a DuPont guideline relief valve (Circle-Seal,set-point pressure 24.5 bar; DuPont, Wilmington, Del.). To furtherprotect the microbalance system from over-pressure, additional reliefvalves were installed on the custom gas manifold and on each gascylinder; these relief valves were set to open if the pressure exceeded25 bar. The reactor over-temperature interlock controller that comesstandard on the IGA003 was set to turn off the water bath if thetemperature exceeded 100° C. Due to the fact that some of the gasestested were flammable (i.e. HFC-32, HFC-143a, and HFC-152a), the IGA003was mounted inside a custom stainless steel cabinet purged with nitrogenthat would minimize the possibility of a flame.

Thermogravimetric measurements were corrected for a number ofgravitational balance forces introduced at high pressure as described byPinkerton, E. P., et al (High-pressure gravimetric measurement ofhydrogen capacity in vapor-grown carbon nanofibers and relatedmaterials. Proceedings of the 11^(th) Canadian Hydrogen Conference,Victoria, BC (2001) pages 633-642). These included:

-   (1) Changes in the buoyant forces due to changes in pressure and    temperature.-   (2) Aerodynamic drag forces created by the flow of gases.-   (3) Changes in the balance sensitivity due to changes in temperature    and pressure.-   (4) Volumetric changes in the samples due to expansivity.

The gravitational balance forces previously described are often of thesame order of magnitude (0.1 to 5 mg) as the overall weight change inthe sample and can lead to inaccurate results if not accounted forprecisely. Distinguishing mass changes with an accuracy of 0.01 wt. % onsmall and sometimes limited sample quantities requires knowledge of thesample weight to within about 5 to 10 μg.

The buoyancy correction follows from Archimedes' principal: there is anupward force exerted on an object equivalent to the mass of fluiddisplaced. The upward force (C_(b)) due to buoyancy is calculated usingeq 1 where the mass of the gas displaced is equivalent to the volume ofthe submersed object (V_(i)) times the density (ρ_(g)) of the gas at agiven (T,P) and the gravitational acceleration (g). If the volume of theobject remains constant, V_(i) can be calculated by knowing the mass(m_(i)) and density (ρ_(i)) of the object. $\begin{matrix}{C_{b} = {{Buoyancy} = {{g\quad V_{i}{\rho_{g}( {T,P} )}} = {g\frac{m_{i}}{\rho_{i}}{\rho_{g}( {T,P} )}}}}} & (1)\end{matrix}$Instead of using the gas densities provided in the Hiden Isochema IGAsoftware, the gas density for each gas was calculated using a computerprogram (REFPROP v.7) developed by the National Institute of Standardsand Technology (NIST) (Lemmon E W, et al. [NIST reference fluidthermodynamic and transport properties —REFPROP, version 7.0 user'sguide, U.S. Department of Commerce, Technology Administration, NationalInstitute of Standards and Technology, Standard Reference Data Program,Gaithersburg, Md., 2002]).

The buoyancy correction using the IGA003 system involves many additionalobjects for weighing the sample. Table 31 provides a list of eachcritical component along with the objects weight, material, density, andtemperature. The component arrangement in FIG. 18 leads to a massbalance as shown by eq 2. This expression accounts for the summation ofall components as well as the contribution of the absorbed gas mass(m_(a)) and a correction factor (C_(f)) which accounts for the balancesensitivity to T P. The density of air (Pair) at ambient temperature andpressure was subtracted from ρ_(i) and σ_(j) because the components wereinitially weighed in air. $\begin{matrix}\begin{matrix}{{\sum\limits_{i = 1}\quad m_{i}} - {\sum\limits_{j = 1}\quad m_{j}} - {\sum\limits_{i = 1}\quad{\frac{m_{i}}{\rho_{i}}{\rho_{g}( {T_{i},P} )}}} + {\sum\limits_{j = 1}\quad{\frac{m_{j}}{\rho_{j}}{\rho_{g}( {T_{j},P} )}}} +} \\{{m_{IL} + m_{a} - {\frac{m_{IL}}{\rho_{s}( T_{s} )}{\rho_{g}( {T_{s},P} )}} - {\frac{m_{a}}{\rho_{a}( T_{s} )}{\rho_{g}( {T_{s},P} )}} -}\quad} \\{{{C_{f}( {T_{s},P} )} = {reading}}\quad}\end{matrix} & (2)\end{matrix}$The largest contributions in eq 2 are typically those of the samplecontainer, sample, and counter weight; the other referenced objects inTable 31 contribute less because of their larger densities (denominatorsin eq 2). Physical densities of ionic liquids were measured using aMicromeritics Accupyc 1330 helium pycnometer with an accuracy of ±0.001g cm⁻³ (Micromeritics Instrument Corp., Norcross, Ga.). Initially, thevolume (V_(IL)) of each sample was calculated from its pycnometricdensity (ρ_(s)) and dry mass sample weight (ρ_(s)), but volumetricexpansion (Δ{tilde over (V)}/{tilde over (V)}₀) due to the gasabsorption was later taken into account as described below to moreaccurately determine the buoyancy effect.

The system was operated in static mode that essentially eliminates anyaerodynamic drag forces due to flowing gases. Electrobalances aresensitive to temperature and pressure fluctuations on the beam arm andinternal electronics. To minimize this effect, the balance electronicsare heated externally with a band heater to a temperature of 45±0.1° C.In addition, the component temperatures provided in Table 31 aremeasured for the sample (T_(s)) and all others are estimated. Therefore,a correction factor (C_(f)) was determined as a function of T, P bymeasuring the buoyancy effect without a sample and calculating aleast-squares fit to tare the balance. The correction factor was on theorder of 0.1 to 0.3 mg and increased as expected with decreasingtemperature and increasing pressure.

Initially the ionic liquid sample volume was considered to be constantand the mole fraction solubility calculated without taking into accountbuoyancy effects due to sample expansivity. In order to make a properbuoyancy correction due to the liquid volume change, a simple molefraction average for the molar volume, {tilde over (V)}_(m), was used.{tilde over (V)} _(m)(T,P)={tilde over (V)} _(IL)(1−x)+{tilde over (V)}_(g) x,  (3)

where {tilde over (V)}_(i)=MW_(i)/ρ_(i) and x represents the molarfraction of gas in the solution. $\begin{matrix}{{V_{m}( {T,P} )} = {{{\overset{\sim}{V}}_{m}( {T,P} )}\lbrack {( \frac{m_{IL}}{{MW}_{IL}} ) + ( \frac{m_{g}}{{MW}_{g}} )} \rbrack}} & (4) \\\begin{matrix}{{{\frac{m_{s}}{\rho_{s}( T_{s} )}{\rho_{g}( {T_{s},P} )}} + {\frac{m_{a}}{\rho_{a}( T_{s} )}{\rho_{g}( {T_{s},P} )}}} =} \\{{{V_{m}( {T,P} )}{\rho_{g}( {T,P} )}}\quad}\end{matrix} & (5)\end{matrix}$As a first approximation, eqs 3 and 4 were used to estimate the changein the liquid sample volume, V_(m), at the measured T, P conditions. Eq5 can be substituted into eq 2 to account for the buoyancy change withrespect to sample expansivity.

Besides the equilibrium solubility, time-dependent absorption data werealso gathered using the Hiden gravimetric microbalance for each T, Pset-point. In order to understand the time-dependent behavior of gasdissolving in liquid, we applied a mathematical model based on asimplified mass diffusion process. Imagine a flat-bottom samplecontainer filled with ionic liquid at a certain liquid level height (L).The height is determined by knowing the cylindrical geometry of thesample container, dry sample weight after evacuation and heating, andthe ionic liquid density at the proper temperature. After evacuation,the gas is introduced into the Pyrex® sample container with a constantpressure at a given temperature. A small amount of gas will startdissolving into the ionic liquid, and after a sufficient time it willreach a thermodynamic equilibrium, that is the solubility limit of thegas in the ionic liquid at the given T and P. This transient behaviorwith time is modeled as described by Shiflett, M. B. and Yokozeki, A.(Ind. Eng. Chem. Research, 2005, 44, 4453-4464) and Yokozeki, A. (Int.J. Refrigeration, 2002, 22, 695-704).

Processes of gas dissolving in liquid may be highly complex phenomenabecause of a possible evolution of heat of mixing, the subsequent liquidconvection due to the local temperature difference, as well as the freeconvection due to the density difference, and the possible change inthermophysical properties of the liquid. The following assumptions weremade for the dissolving gas (Shiflett, M. B., and Yokozeki, A. (supra);and Yokozeki, A (Time-dependent behavior of gas absorption in lubricantoil [Int. J. Refrigeration (2002), 22, 695-704]):

-   (1) Gas dissolves through a one-dimensional (vertical) diffusion    process, in which there is no convective flow in the liquid.-   (2) A thin boundary layer between the gas and liquid phases exists,    where the thermodynamic equilibrium is instantly established with    the saturation concentration (C_(s)), and where the concentration is    constant all the time at a given temperature and pressure.-   (3) Temperature and pressure are kept constant.-   (4) The gas-dissolved liquid is a highly dilute solution, and so the    relevant thermophysical properties of the solution do not change.    The process may then be described by one-dimensional mass diffusion    due to the local concentration difference. The governing    differential equations are: $\begin{matrix}    {\frac{\partial C}{\partial t} = {D\frac{\partial^{2}C}{\partial z^{2}}}} & (6) \\    {{{Initial}\quad{{Condition}:\quad C}} = {{C_{0}\quad{when}\quad t} = {{0\quad{and}\quad 0} < z < L}}} & (7) \\    {{{Boundary}\quad{{Conditions}:\quad C}} = {{{C_{s}\quad{when}\quad t} > {0\quad{and}\quad z}} = 0}} & (8) \\    {\frac{\partial C}{\partial z} = {{0\quad{at}\quad z} = L}} & (9)    \end{matrix}$    Where C is the concentration of a dissolving substance in ionic    liquid as a function of time, t and vertical location, z, where L is    the depth of ionic liquid in the container, and z=0 corresponds to    the vapor-liquid boundary. C₀ is an initial homogenous concentration    of the dissolving gas, and is zero (initially) or a small finite    amount at t>0. D is the diffusion coefficient that is assumed to be    constant.

Eq 6 can be solved analytically for the initial and boundary conditionseqs 7-9 by a standard method such as separation variables or Laplacetransform and yields: $\begin{matrix}\begin{matrix}{{C = {C_{S}\lbrack {1 - {2( {1 - \frac{C_{0}}{C_{S}}} ){\sum\limits_{n = 0}^{\infty}\quad\frac{{\exp( {{- \lambda_{n}^{2}}D\quad t} )}\sin\quad\lambda_{n}z}{L\quad\lambda_{n}}}}} \rbrack}},} \\{{{where}\quad\lambda_{n}} = {( {n + \frac{1}{2}} ){\frac{\pi}{L}.}}}\end{matrix} & (10)\end{matrix}$An experimentally observed quantity at a specified time is the totalconcentration (or mass) of dissolved gas in ionic liquid, and not theconcentration profile in z. This space-averaged concentration at a giventime, <C>, can be calculated from eq 11. $\begin{matrix}{< C>={\int_{0}^{L}{C\quad{{\mathbb{d}z}/L}}}} & (11) \\{< C>={C_{S}\lbrack {1 - {2( {1 - \frac{C_{0}}{C_{S}}} ){\sum\limits_{n = 0}^{\infty}\quad\frac{\exp( {{- \lambda_{n}^{2}}D\quad t} )}{L^{2}\lambda_{n}^{2}}}}} \rbrack}} & (12)\end{matrix}$

Although eq 12 contains an infinite summation, only the first few terms,except for initial small time periods, are sufficient in practicalapplications. In this work, the summation was terminated after ten termswhen the numerical contribution to the summation in <C> became less than10-12. By analyzing experimental data with this equation, we obtainedthe saturation concentration (C_(s)) and diffusion constant (D) at givenT and P, when C₀ was known.

Properties of Lubricants and Lubricant/Refrigerant Mixtures

For vapor compression refrigeration and air-conditioning applications,the viscosity, density, and molecular weight of the lubricating oil areimportant properties. The viscosity of the oil and the solubility of therefrigerant in the oil are the two key factors in good oil return to thecompressor. The viscosity of the oil cannot be so high that the oilbecomes viscous at lower temperatures or so low that it does notlubricate the compressor properly at high temperatures. A viscosity ofabout 150 Saybolt universal seconds (SUS) or about 30-35 centipoise (cP)at 37.8° C. (100° F.) is generally used for low and medium temperaturerefrigeration applications. A viscosity of about 300 SUS or about 50-60cP at 37.8° C. (100° F.) is generally used for higher temperatureair-conditioning applications. The division, however, is not exact andboth viscosities can be used for low temperature applications. Evenhigher viscosity oils such as 500 SUS are used in mobileair-conditioning applications. Examples of mineral oils that werecommonly used with chlorofluorocarbon (CFC) refrigerants are Suniso 3GS,4GS, and 5GS (Sun Oil Company) with viscosities of 150, 300, and 500SUS, respectively.

The densities of the three Suniso oils are about 0.91 to 0.92 g cm⁻³ at21.1° C. (70° F.). The molecular weight can vary from about 300 to 330 ggmol⁻¹. The properties of these products can vary since they are naturalor mineral-based oils (MO) derived from underground petroleum sourceswhich are a complex mixture of chemical compounds; the composition mayalso vary with drilling location and time (Downing, R. C. FluorocarbonRefrigerants Handbook, Prentice-Hall, 1988).

Many ionic liquids have the proper viscosity, density, and molecularweight range to be used as lubricants as shown in Example 1, Table 1.For vapor compression heating or cooling systems the lubricant must besoluble in the refrigerant such that the lubricant that escapes thecompressor and becomes entrained with the refrigerant is returned to thecompressor. In addition, the mixture properties of the refrigerant andlubricant must adequately perform as a lubricant in the compressor.

The viscosity of oil with dissolved refrigerant is the key factor in oilreturn since the oil is moved by the force of the flowing refrigerantand thin oil moves better than thick or viscous oil. Temperature is alsoan important factor, but ultimately the mixture viscosity properties ofthe oil and refrigerant dominate the ability of the oil to return to thecompressor.

Several measurements of the viscosity of oil-refrigerant solutions havebeen reported (Downing, R. C. Fluorocarbon Refrigerants Handbook,Prentice-Hall, 1988). In order to have the proper lubrication in thecompressor, the mixture viscosity should be similar to the mixtureviscosity of the traditional refrigerant-oil working fluid. Forillustration, the viscosity of the mixtures of the refrigerantchlorodifluoromethane (HCFC-22) with several SUNISO lubricants werecompared to that of refrigerant-ionic liquid working fluids useful forthe invention. (see Example 2, Table 2).

EXAMPLE 1

Viscosity, density, and molecular weight comparison of ionic liquidswith SUNISO 3GS, 4GS, and 5GS mineral oils are shown in Table 1(Downing, R. C., supra). TABLE 1 Ionic Liquid Viscosity DensityMolecular at 40° C. at 21° C. Weight (cP or mPa · s) (g cm⁻³) (g mol⁻¹)SUNISO 3GS 27 0.91 300-330 SUNISO 4GS 51 0.92 300-330 SUNISO 5GS 87 0.92300-330 [bmim][PF₆] 147 1.37 284.2 [bmim][BF₄] 59 1.21 226.0[dmpim][TMeM] 239 1.60 551.5 [emim][BEI] 44 1.59 491.3 [emim][BMeI] 201.52 391.3 [dmpim][BMeI] — — 419.4 [pmpy][BMeI] 31 1.45 416.4[bmpy][BMeI] — 1.42 430.4 [emim][TFES] —  1.50* 292.3 [bmim][TFES] — 1.32* 320.3 [dmim][TFES] —  1.14* 432.5 [hmim][TFES] —  1.27* 362.4[bmim][Ac] —  1.05** 198.3 [bmim][MeSO₄] —  1.21** 250.3 [bmim][SCN] — 1.07** 197.3 [bmim][FS] — 1.45 436.3 [bmim][HFPS] 108 1.41 370.3[bmim][TPES] 119 1.43 436.3 [bmim][TTES] 93 1.40 386.3[6,6,6,14-P][TPES] 191 1.07 780.0 [4,4,4,14-P][HFPS] 289 1.07 629.4*T = 28.3° C.,**T = 25-26° C.

EXAMPLE 2

The concentration of the refrigerant in the ionic liquid (or oil) andviscosity of the refrigerant and ionic liquid (or oil) mixtures werecalculated and compared with chlorodifluoromethane (HCFC-22) and thethree SUNISO lubricants (3GS, 4GS, and 5GS) (see Downing, R. C.,(supra)). The temperature in all cases was 40° C. and the lubricationeffectiveness was evaluated as excellent, good, average, or poor basedon how close the viscosity of the mixture compared with HCFC-22 and theSUNISO lubricants as shown in Table 2. Five mixtures were rated as“excellent”: HFC-134a and [bmim][PF₆], HFC-152a and [bmim][PF₆],HFC-134a and [bmim][TPES], HFC-134a and [bmim][TTES], and HFC-134a and[4,4,4,14-P][HFPS]. Three refrigerant-ionic liquid mixtures wereevaluated with a “good” lubrication performance: HFC-143a and[bmim][PF₆], HFC-134a and [bmim][HFPS], and HFC-134a and[6,6,6,14-P][TPES]. In addition, four refrigerant-ionic liquid mixtureswere evaluated to have “average” lubrication performance: HFC-134a and[emim][BEI], HFC-32 and [bmim][BF₄], HFC-125 and [bmim][PF₆], and HFC-32and [bmim]PF₆]. Finally, several mixtures were found to have “poor”lubrication performance because the viscosity of the mixture was too lowcompared with HCFC-22 and the SUNISO lubricants. Those mixtures includedHFC-32 with [dmpim][TMeM], [emim][BEI], [pmpy][BMeI], [emim][BMeI],[bmim][HFPS], [bmim][TPES], and [bmim][TTES]. Although HFC-32 has a highsolubility in the ionic liquid which reduces the viscosity of themixture, it also most not decrease the viscosity so much that themixture viscosity is too low for providing adequate lubrication in thecompressor. Therefore, ionic liquids with higher molecular weights maywork better with the HFC-32 refrigerant for lubricating the compressor.TABLE 2 Refrigerant Mixture Lubri- in Vis- cation Refrig- Lubricantcosity Effective- erant Lubricant (mass %) (cp) ness HCFC-22 SUNISO 3GS10 10 Excellent HCFC-22 SUNISO 4GS 10 16 Excellent HCFC-22 SUNISO 5GS 1023 Excellent HFC-32 [bmim][PF₆] 20 4 Average HFC-125 [bmim][PF₆] 10 48Average HFC-134a [bmim][PF₆] 15 26 Excellent HFC-143a [bmim][PF₆] 10 31Good HFC-152a [bmim][PF₆] 15 13 Excellent HFC-32 [bmim][BF₄] 20 4Average HFC-32 [dmpim][TMeM] 20 1 Poor HFC-32 [emim][BEI] 20 1 PoorHFC-32 [pmpy][BMeI] 20 1 Poor HFC-32 [emim][BMeI] 20 1 Poor HFC-32[bmim][HFPS] 20 2 Poor HFC-32 [bmim][TPES] 20 2 Poor HFC-32 [bmim][TTES]20 2 Poor HFC-134a [emim][BEI] 15 6 Average HFC-134a [bmim][HFPS] 15 15Good HFC-134a [bmim][TPES] 15 12 Excellent HFC-134a [bmim][TTES] 15 13Excellent HFC-134a [6,6,6,14-P][TPES] 15 6 Good HFC-134a[4,4,4,14-P][HFPS] 15 10 Excellent

Examples 3-35 provide solubility and diffusivity results for severalhydrofluorocarbon refrigerants. These data are used for solubility withlubricant in Examples 1 and 2.

Examples 3-7 and FIGS. 3-7 show solubility and diffusivity results forseveral hydrofluorocarbons (HFC-32, HFC-125, HFC-134a, HFC-143a, andHFC-152a) in one ionic liquid, [bmim][PF₆], at 10, 25, 50, and 75° C.Compositions were prepared that consisted of HFC-32 and [bmim][PF₆] fromabout 0.3 to about 81.2 mole percent of HFC-32 over a temperature rangefrom 10 to 75° C. at a pressure from about 0.1 to 10 bar. Compositionswere prepared that consisted of HFC-125 and [bmim][PF₆] from about 0.1to about 65.1 mole percent of HFC-125 over a temperature range from 10to 75° C. at a pressure from about 0.1 to 10 bar. Compositions wereprepared that consisted of HFC-134a and [bmim][PF₆] from about 0.1 toabout 72.1 mole percent of HFC-134a over a temperature range from 10 to75° C. at a pressure from about 0.1 to 3.5 bar. Compositions wereprepared that consisted of HFC-143a and [bmim][PF₆] from about 0.1 toabout 26.5 mole percent of HFC-143a over a temperature range from 10 to75° C. at a pressure from about 0.1 to 7.5 bar. Compositions wereprepared that consisted of HFC-152a and [bmim][PF₆] from about 0.5 toabout 79.7 mole percent of HFC-152a over a temperature range from 10 to75° C. at a pressure from about 0.1 to 4.5 bar.

Examples 8-14 and 17-29 and FIGS. 8, 11-16 show solubility anddiffusivity results for HFC-32 in several additional ionic liquids.Examples 15 and 16 and FIGS. 9 and 10 show solubility and diffusivityresults for HFC-23 in the ionic liquids [bmim][PF₆] and [emim][PF₆].

Examples 30-35 show solubility and diffusivity results for HFC-134a inseveral ionic liquids.

Compositions were prepared that consisted of HFC-32 and [bmim][BF₄] fromabout 0.1 to about 76.5 mole percent of HFC-32 over a temperature rangefrom 10 to 75° C. at a pressure from about 0.1 to 10 bar. Compositionswere prepared that consisted of HFC-32 and [dmpim][TMeM] from about 0.9to about 66 mole percent of HFC-32 at a temperature of 25° C. and apressure from about 0.1 to 10 bar. Compositions were prepared thatconsisted of HFC-32 and [omim][I] from about 0.4 to about 41.6 molepercent of HFC-32 at a temperature of 25° C. and a pressure from about0.1 to 10 bar. Compositions were prepared that consisted of HFC-32 and[doim][I] from about 0.7 to about 46.8 mole percent of HFC-32 at atemperature of 25° C. and a pressure from about 0.1 to 10 bar.Compositions were prepared that consisted of HFC-32 and [emim][BEI] fromabout 1.0 to about 66.6 mole percent of HFC-32 at a temperature of 25°C. and a pressure from about 0.1 to 10 bar. Compositions were preparedthat consisted of HFC-32 and [dmpim][TMeM] from about 0.8 to about 64.5mole percent of HFC-32 at a temperature of 25° C. and a pressure fromabout 0.1 to 10 bar. Compositions were prepared that consisted of HFC-32and [pmpy][BMeI] from about 1.0 to about 63.9 mole percent of HFC-32 ata temperature of 25° C. and a pressure from about 0.1 to 10 bar.Compositions were prepared that consisted of HFC-32 and [emim][BMeI]from about 0.1 to about 78.5 mole percent of HFC-32 over a temperaturerange from 10 to 75° C. at a pressure from about 0.1 to 10 bar.Compositions were prepared that consisted of HFC-32 and [bmpy][BMeI]from about 1.0 to about 64.8 mole percent of HFC-32 at a temperature of25° C. and a pressure from about 0.1 to 10 bar. Compositions wereprepared that consisted of HFC-32 and [emim][TFES] from about 1.0 toabout 47.1 mole percent of HFC-32 at a temperature of 25° C. and apressure from about 0.1 to 10 bar. Compositions were prepared thatconsisted of HFC-32 and [bmim][TFES] from about 1.0 to about 55.0 molepercent of HFC-32 at a temperature of 25° C. and a pressure from about0.1 to 10 bar. Compositions were prepared that consisted of HFC-32 and[odmim][TFES] from about 1.0 to about 56.2 mole percent of HFC-32 at atemperature of 25° C. and a pressure from about 0.1 to 10 bar.Compositions were prepared that consisted of HFC-32 and [hmim][TFES]from about 1.0 to about 58.6 mole percent of HFC-32 at a temperature of25° C. and a pressure from about 0.1 to 10 bar. Compositions wereprepared that consisted of HFC-23 and [bmim][PF₆] from about 0.1 toabout 52.8 mole percent of HFC-23 over a temperature range from 10 to75° C. at a pressure from about 0.1 to 20 bar. Compositions wereprepared that consisted of HFC-23 and [emim][PF₆] from about 0.1 toabout 15.1 mole percent of HFC-23 over a temperature range from 60 to75° C. at a pressure from about 0.1 to 20 bar.

FIG. 17 shows measured isothermal solubility data (in mole fraction) at10° C. of the systems HFC-32, HFC-152a, HFC-134a, HFC-125, andHFC-143a+[bmim][PF₆] in terms of absolute pressure divided by the gassaturation pressure (P₀) at 10° C. shown by ratio (P/P₀). The saturationpressures for HFC-32, HFC-125, HFC-134a, HFC-143a, and HFC-152a at 10°C. are P₀=11.069 bar, P₀=3.7277 bar, P₀=4.1461 bar, P₀=9.0875, andP₀=8.3628 bar, respectively. Negative deviations from Raoult's law (i.e.curvature below the dashed line) indicate strong interaction between therefrigerant and the ionic liquid, which indicates high solubility. Inparticular HFC-32 has negative deviation from Raoult's law as shown inFIG. 17. Compositions comprise HFC-32 and [bmim][PF₆] from about 0.1 to63 mole percent of HFC-32 at 10° C. and P/P₀ from about 0.1 to about0.63. Strong positive deviations from Raoult's law (i.e. curvature abovethe dashed line) are more typical and indicate refrigerant and ionicliquids are less soluble and eventually may form a liquid-liquid phaseseparation. Compositions comprise HFC-152a and [bmim][PF₆] from about0.1 to about 80 mole percent of HFC-152a at 10° C. and P/P₀ from 0.1 toabout 0.86. Compositions comprise HFC-134a and [bmim][PF₆] from about0.1 to about 72 mole percent of HFC-134a at 10° C. and P/P₀ from about0.1 to about 0.84. Compositions comprise HFC-125 and [bmim][PF₆] fromabout 0.1 mole to about 65 mole percent of HFC-125 at 10° C. and P/P₀from about 0.1 to about 0.88. Compositions comprise HFC-143a and[bmim][PF₆] from about 0.1 to about 25 mole percent at 10° C. and P/P₀from about 0.1 to about 0.90.

Example 36 provides details about the components of the microbalance.

Examples 37-38 show solubility and diffusivity results for CO₂ in twodifferent ionic liquids.

EXAMPLE 3

Solubility of difluoromethane (HFC-32) in 1-butyl-3-methylimidazoliumhexafluorophosphate [bmim][PF₆]

A solubility and diffusivity study was made at temperatures of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(e)), and calculated solubility (X_(calc.))are also provided.

Tables 4a, 4b, 4c and 4d provide data for C_(o), C_(s), D, X_(calc), andX_(meas) at temperatures of 10, 25, 50 and 75° C., respectively. TABLE4a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol. (° C.)(bar) %) %) (m²/sec) fraction) fraction) 10.0 0.0979 0.52 0.54 1.54E−090.029 0.026 10.0 0.9957 0.82 2.53 1.94E−11 0.124 0.106 10.0 2.4967 3.327.56 1.71E−11 0.309 0.270 10.0 3.9964 8.18 12.38 3.65E−11 0.436 0.42610.0 5.4975 14.44 18.71 6.34E−11 0.557 0.555 10.0 6.9965 22.12 27.857.42E−11 0.678 0.676 10.0 8.4954 — — — — 0.812

TABLE 4b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.0965 0.16 0.211.84E−10 0.012 0.018 25.0 0.9952 0.49 1.69 2.45E−11 0.086 0.076 25.02.4965 2.22 4.53 2.44E−11 0.206 0.189 25.0 3.9979 5.05 7.37 3.51E−110.303 0.295 24.9 5.4969 8.23 10.47 5.41E−11 0.390 0.387 24.9 6.995011.82 14.09 6.75E−11 0.473 0.471 25.0 8.5012 15.75 18.26 8.33E−11 0.5500.548 24.9 9.9994 20.38 23.31 8.84E−11 0.624 0.622

TABLE 4c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 49.6 0.0992 0.00 0.124.76E−11 0.007 0.006 49.9 0.9954 0.33 0.92 5.28E−11 0.048 0.047 49.92.4963 1.43 2.31 5.29E−11 0.115 0.113 49.9 3.9949 2.84 3.72 5.98E−110.174 0.173 49.9 5.4966 4.41 5.22 5.99E−11 0.231 0.229 49.9 6.9965 5.816.72 7.69E−11 0.282 0.282 50.0 8.4959 7.37 8.32 8.54E−11 0.331 0.33150.0 9.9959 9.78 10.05 4.04E−11 0.379 0.377

TABLE 4d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.0988 0.00 0.067.12E−11 0.003 0.003 75.0 0.9968 0.30 0.56 8.19E−11 0.030 0.029 75.02.4950 0.96 1.38 8.14E−11 0.071 0.069 75.0 3.9944 1.74 2.19 9.82E−110.109 0.108 74.9 5.4983 2.60 3.03 9.70E−11 0.146 0.145 74.9 6.9966 3.423.89 9.58E−11 0.181 0.180 75.0 8.4958 4.28 4.77 9.56E−11 0.215 0.21275.0 9.9989 5.12 5.62 1.18E−10 0.245 0.244

EXAMPLE 4

Solubility of pentafluoroethane (HFC-125) in 1-butyl-3-methylimidazoliumhexafluorophosphate [bmim][PF₆]

A solubility and diffusivity study was made at temperatures of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 5a, 5b, 5c and 5d provide data for C_(o), C_(s), D, X_(calc), andX_(meas) at temperatures of 10, 25, 50 and 75° C., respectively. TABLE5a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol. (° C.)(bar) %) %) (m²/sec) fraction) fraction) 9.9 0.0992 0.0 0.12 2.52E−120.003 0.013 10.0 0.9964 0.73 1.50 1.83E−11 0.035 0.034 10.1 1.9959 1.723.96 6.36E−12 0.089 0.074 10.0 2.9960 3.55 6.25 9.31E−12 0.136 0.12510.1 3.9964 6.03 8.88 1.56E−11 0.187 0.182 9.9 4.9965 9.10 12.522.44E−11 0.253 0.250 10.0 5.9965 13.18 17.56 4.05E−11 0.335 0.336 9.96.9962 19.19 26.04 6.12E−11 0.455 0.454 10.0 7.9979 — — — — 0.651

TABLE 5b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.0 0.0977 0.0 0.093.29E−12 0.002 0.003 25.0 0.9963 0.23 0.09 1.81E−11 0.002 0.023 25.01.9982 1.05 2.12 1.50E−11 0.049 0.050 24.9 2.9949 2.13 3.11 2.15E−110.071 0.079 25.0 3.9982 3.50 4.71 2.03E−11 0.105 0.109 25.0 4.9947 4.846.18 2.39E−11 0.135 0.140 25.0 5.9951 6.38 7.91 2.65E−11 0.169 0.17625.0 7.9955 8.96 12.10 4.81E−11 0.246 0.254 24.9 9.9977 14.20 18.167.82E−11 0.344 0.352

TABLE 5c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 49.9 0.1003 0.0 0.021.96E−10 0.000 0.000 49.9 0.9963 0.18 0.55 4.29E−11 0.013 0.013 49.91.9983 0.73 1.17 4.59E−11 0.027 0.027 50.0 2.9996 1.34 1.78 5.19E−110.041 0.041 49.9 3.9969 1.96 2.44 4.75E−11 0.056 0.056 50.0 4.9993 2.603.10 5.38E−11 0.070 0.070 49.9 5.9961 3.29 3.80 5.14E−11 0.086 0.08549.9 7.9970 4.38 5.25 5.55E−11 0.116 0.116 49.9 9.9958 5.85 6.825.87E−11 0.148 0.148

TABLE 5d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.1021 0.0 0.036.85E−10 0.001 0.001 74.9 0.9965 0.07 0.28 7.49E−11 0.007 0.007 75.01.9961 0.36 0.60 9.46E−11 0.014 0.016 75.1 2.9967 0.70 0.93 7.04E−110.022 0.025 75.0 3.9971 1.04 1.27 7.96E−11 0.030 0.033 75.0 4.9983 1.361.61 9.86E−11 0.037 0.042 75.0 5.9980 1.75 1.97 7.12E−11 0.045 0.05275.1 7.9997 2.26 2.65 1.14E−10 0.061 0.068 75.0 9.9959 3.00 3.338.89E−11 0.075 0.085

EXAMPLE 5 Solubility of 1,1,1,2-tetrafluoroethane (HFC-134a) in1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆]

A solubility and diffusivity study was made at temperatures of 10, 25,50, and 75° C. over a pressure range from 0 to 3.5 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 6a, 6b, 6c and 6d provide data for C_(o), C_(s), D, X_(calc), andX_(meas) at temperatures of 10, 25, 50 and 75° C., respectively. TABLE6a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 9.8 0.0999 0.0 0.234.21E−12 0.006 0.003 10.0 0.4981 0.35 2.20 6.46E−12 0.059 0.050 9.90.9986 2.25 5.73 5.78E−12 0.145 0.126 9.9 1.4981 5.40 9.15 1.01E−110.219 0.212 9.9 2.0024 9.50 13.64 1.48E−11 0.306 0.303 9.9 2.4907 14.3919.36 2.67E−11 0.401 0.402 9.9 2.9974 20.96 27.51 5.33E−11 0.514 0.5169.9 3.4900 — — — — 0.721

TABLE 6b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.0 0.1002 0.170.29 4.36E−12 0.008 0.011 24.9 0.4981 0.57 1.52 1.89E−11 0.041 0.04225.0 0.9972 1.82 3.26 1.71E−11 0.086 0.085 25.0 1.4987 3.60 5.092.00E−11 0.130 0.130 25.0 1.9930 5.43 7.09 2.27E−11 0.175 0.175 24.92.4996 7.53 9.31 2.59E−11 0.222 0.222 25.0 2.9952 9.78 11.82 2.82E−110.272 0.273 24.9 3.5000 12.51 14.62 3.99E−11 0.323 0.323

TABLE 6c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 49.9 0.0992 0.07 0.132.44E−11 0.004 0.004 50.0 0.4984 0.25 0.75 4.39E−11 0.021 0.021 49.90.9971 1.00 1.57 3.94E−11 0.043 0.043 49.9 1.4989 1.79 2.42 4.48E−110.064 0.065 50.0 1.9895 2.65 3.28 4.38E−11 0.086 0.086 50.0 2.4900 3.754.23 2.33E−11 0.110 0.108 50.0 2.9897 4.43 5.10 4.90E−11 0.130 0.13050.0 3.4933 5.39 6.06 5.00E−11 0.152 0.152

TABLE 6d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.0970 0.00 0.036.45E−11 0.001 0.001 74.9 0.4984 0.09 0.32 7.49E−11 0.009 0.009 74.90.9934 0.51 0.79 7.93E−11 0.022 0.022 74.9 1.5010 0.98 1.27 7.78E−110.035 0.035 75.0 1.9983 1.44 1.73 8.37E−11 0.047 0.046 75.0 2.5014 1.892.21 8.37E−11 0.059 0.059 75.0 3.0022 2.39 2.71 8.26E−11 0.072 0.07275.0 3.4897 2.95 3.21 5.53E−11 0.085 0.084

EXAMPLE 6 Solubility of 1,1,1-trifluoroethane (HFC-143a) in1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆]

A solubility and diffusivity study was made at temperatures of 10, 25,50, and 75° C. over a pressure range from 0 to 7.5 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 7a, 7b, 7c and 7d provide data for C_(o), C_(s), D, X_(calc), andX_(meas) at temperatures of 10, 25, 50 and 75° C., respectively. TABLE7a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol. (° C.)(bar) %) %) (m²/sec) fraction) fraction) 11.7 0.0956 0.03 0.10 8.10E−120.003 0.003 12.0 0.9970 0.22 0.92 8.51E−12 0.031 0.029 11.9 1.9830 0.991.93 8.11E−12 0.064 0.060 12.0 2.9740 1.95 2.39 3.21E−12 0.078 0.09312.3 3.9808 3.06 4.03 1.04E−11 0.127 0.124 12.0 4.9975 4.16 5.231.10E−11 0.161 0.156 12.0 5.9821 5.30 6.42 1.44E−11 0.192 0.188 12.26.9975 6.54 7.63 1.94E−11 0.223 0.219 12.2 7.4832 7.80 8.31 2.03E−110.239 0.235

TABLE 7b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.0 0.0951 0.00 0.011.53E−11 0.001 0.004 24.9 0.9970 0.24 0.69 2.05E−11 0.023 0.023 24.92.0054 0.84 1.33 2.56E−11 0.045 0.042 24.9 2.9895 1.40 2.10 1.83E−110.069 0.068 24.9 4.0147 2.26 2.89 1.77E−11 0.093 0.090 24.9 4.9886 2.953.60 2.24E−11 0.114 0.112 24.9 5.9855 3.71 4.33 2.73E−11 0.136 0.13424.9 7.0019 4.47 5.12 2.83E−11 0.157 0.155 24.9 7.5011 5.14 5.533.61E−11 0.169 0.165

TABLE 7c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 49.9 0.1050 0.00 0.031.51E−10 0.000 0.001 49.9 1.0023 0.16 0.40 4.47E−11 0.014 0.013 50.12.0045 0.61 0.84 3.41E−11 0.028 0.027 50.0 3.0002 1.03 1.26 2.90E−110.042 0.040 50.0 4.0021 1.39 1.65 5.08E−11 0.055 0.054 50.0 5.0046 1.812.08 4.10E−11 0.069 0.067 50.0 6.0039 2.29 2.50 3.75E−11 0.082 0.07950.0 7.0029 2.63 2.90 5.57E−11 0.094 0.092 50.0 10.0030 3.56 4.165.51E−11 0.131 0.127

TABLE 7d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.0995 0.00 0.013.86E−12 0.000 0.001 74.9 1.0005 0.18 0.26 7.38E−11 0.009 0.009 74.81.9960 0.38 0.54 1.04E−10 0.018 0.018 74.9 3.0001 0.67 0.81 1.07E−100.028 0.027 74.9 4.0015 0.91 1.08 1.32E−10 0.037 0.036 74.9 5.0027 1.181.36 1.20E−10 0.045 0.044 75.0 5.9979 1.44 1.63 1.40E−10 0.054 0.05375.0 7.0026 1.92 1.94 3.79E−09 0.064 0.061 74.9 10.0035 2.65 2.761.90E−09 0.089 0.083

EXAMPLE 7 Solubility of 1,1-difluoroethane (HFC-152a) in1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆]

A solubility and diffusivity study was made at temperatures of 10, 25,50, and 75° C. over a pressure range from 0 to 4.5 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 8a, 8b, 8c and 8d provide data for C_(o), C_(s), D, X_(calc), andX_(meas) at temperatures of 10, 25, 50 and 75° C., respectively. TABLE8a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol. (° C.)(bar) %) %) (m²/sec) fraction) fraction) 10.0 0.0973 0.10 0.73 2.13E−120.031 0.021 10.0 0.4994 1.23 2.90 1.14E−11 0.114 0.103 10.0 0.9933 3.586.11 1.56E−11 0.219 0.210 10.0 1.4985 6.91 9.60 3.09E−11 0.314 0.301 9.92.0011 10.40 14.00 3.60E−11 0.412 0.407 9.9 2.4952 15.52 20.42 6.44E−110.525 0.521 9.9 3.1963 — — — — 0.797

TABLE 8b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.0 0.1002 0.16 0.662.00E−11 0.028 0.030 25.0 0.5006 1.02 1.92 2.01E−11 0.078 0.077 24.90.9982 2.34 3.55 2.64E−11 0.137 0.136 25.0 1.4924 4.20 5.35 2.89E−110.196 0.194 25.0 2.4969 6.74 9.52 4.96E−11 0.312 0.311 25.0 3.4818 11.5915.05 7.73E−11 0.433 0.432 25.0 4.5051 18.83 23.81 1.04E−10 0.573 0.574

TABLE 8c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.1 0.9921 0.03 0.155.73E−11 0.007 0.007 50.0 1.0017 0.88 1.46 5.52E−11 0.060 0.060 50.01.5020 1.63 2.22 5.94E−11 0.089 0.089 50.0 2.4969 2.72 3.81 6.43E−110.145 0.145 50.0 4.5051 6.31 7.33 7.88E−11 0.254 0.254

TABLE 8d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.1032 0.04 0.111.38E−10 0.005 0.005 74.9 0.5019 0.19 0.42 1.25E−10 0.018 0.018 74.91.0023 0.57 0.84 1.21E−10 0.035 0.035 74.9 1.5014 0.99 1.27 1.25E−100.052 0.052 75.0 2.4964 1.63 2.12 1.42E−10 0.085 0.085 75.0 3.4970 2.572.98 1.48E−10 0.117 0.117 74.8 4.5003 3.51 3.89 1.21E−10 0.148 0.149

EXAMPLE 8 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium tetrafluoroborate [bmim][BF₄]

A solubility and diffusivity study was made at temperatures of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 9a, 9b, 9c and 9d provide data for C_(o), C_(s), D, X_(calc), andX_(meas) at temperatures of 10, 25, 50 and 75° C., respectively. TABLE9a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol. (° C.)(bar) %) %) (m²/sec) fraction) fraction) 9.9 0.1002 8.35 9.20 1.76E−110.008 0.009 9.9 0.9985 10.08 13.74 1.72E−11 0.100 0.108 10.0 2.499515.10 18.94 3.29E−11 0.239 0.254 10.0 3.9954 21.28 25.08 4.53E−11 0.3760.396 9.8 5.4992 28.16 33.17 8.48E−11 0.499 0.519 9.9 6.9988 37.79 46.861.08E−10 0.625 0.636 9.9 8.4966 52.61 52.61 1.01E−10 0.766 0.765

TABLE 9b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.0 0.0969 0.01 0.153.37E−11 0.007 0.006 25.0 0.9968 0.59 1.81 3.36E−11 0.074 0.070 25.02.4955 2.75 4.79 3.70E−11 0.180 0.174 25.0 3.9989 5.87 7.95 4.62E−110.273 0.270 25.0 5.4977 9.23 11.36 5.98E−11 0.358 0.356 25.0 6.995512.90 15.12 7.44E−11 0.436 0.434 25.0 8.4945 17.08 19.33 9.10E−11 0.5100.510 25.0 9.9985 21.83 24.46 9.94E−11 0.585 0.583

TABLE 9c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.0977 0.01 0.078.71E−11 0.003 0.003 49.9 0.9961 0.37 0.95 7.56E−11 0.040 0.039 50.02.4967 1.67 2.47 7.40E−11 0.099 0.099 50.0 3.9964 3.16 4.01 8.23E−110.154 0.153 49.9 5.4956 4.75 5.59 8.95E−11 0.205 0.204 49.9 6.9953 6.387.22 9.88E−11 0.253 0.253 49.8 8.4986 8.05 8.91 1.06E−10 0.298 0.29850.0 9.9963 9.75 10.64 1.11E−10 0.341 0.341

TABLE 9d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.0971 0.0 0.031.26E−10 0.001 0.001 74.9 0.9956 0.26 0.54 1.28E−10 0.023 0.023 74.92.4948 1.03 1.40 1.25E−10 0.058 0.058 75.0 3.9950 1.92 2.27 1.22E−100.092 0.091 74.9 5.4951 2.75 3.14 1.45E−10 0.124 0.123 75.0 6.9955 3.644.03 1.59E−10 0.154 0.154 74.9 8.4964 4.54 4.94 1.42E−10 0.184 0.18374.9 9.9994 5.44 5.82 1.89E−10 0.212 0.212

EXAMPLE 9 Solubility of difluoromethane (HFC-32) in1,2-dimethyl-3-propylimidazolium tris(trifluoromethylsulfonyl)methide[dmpim][TMeM]

A solubility and diffusivity study was made at temperatures of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 10a, 10b, 10c and 10d provide data for C_(o), C_(s), D, X_(calc),and X_(meas) at temperatures of 10, 25, 50 and 75° C., respectively.TABLE 10a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 10.0 0.1010 0.03 0.111.71E−11 0.012 0.012 10.0 0.9964 0.43 1.44 1.39E−11 0.134 0.136 10.02.4970 2.39 4.13 2.52E−11 0.313 0.311 10.0 3.9969 5.57 7.39 5.04E−110.458 0.457 10.0 5.4947 9.70 11.67 8.93E−11 0.583 0.583 10.0 6.996615.43 17.70 1.37E−10 0.695 0.696 10.0 8.4959 24.33 28.09 1.56E−10 0.8050.802

TABLE 10b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.0998 0.01 0.092.71E−11 0.010 0.010 24.9 0.9997 0.42 1.01 2.52E−11 0.098 0.096 24.92.4956 — — — — 0.225 24.9 3.9958 3.61 4.55 5.46E−11 0.336 0.335 24.95.4927 5.76 6.69 7.98E−11 0.432 0.431 24.9 6.9955 8.15 9.13 1.10E−100.516 0.515 24.9 8.4948 11.02 12.07 1.34E−10 0.593 0.593 24.9 10.000014.52 15.59 1.83E−10 0.662 0.662

TABLE 10c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.0991 0.21 0.046.45E−11 0.004 0.004 50.0 0.9995 0.29 0.57 6.75E−11 0.058 0.057 50.02.4945 1.11 1.52 7.87E−11 0.141 0.141 50.0 3.9947 2.10 2.50 9.56E−110.213 0.213 50.0 5.4954 3.15 3.51 1.15E−10 0.278 0.278 50.0 6.9968 4.244.59 1.33E−10 0.338 0.338 50.0 8.4944 5.37 5.73 1.51E−10 0.392 0.39250.0 9.9952 6.61 6.96 1.68E−10 0.442 0.442

TABLE 10d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.0940 0.0 0.05.75E−11 0.000 0.000 74.9 1.0018 0.06 0.31 6.06E−11 0.032 0.031 75.02.5040 0.71 0.89 1.23E−10 0.087 0.087 74.9 3.9958 1.32 1.49 1.26E−100.138 0.138 74.9 5.4938 1.92 2.09 1.59E−10 0.184 0.184 74.9 7.0051 2.582.72 1.35E−10 0.229 0.229 74.9 8.4954 3.24 3.37 1.19E−10 0.270 0.26874.9 10.0046 3.89 4.05 2.10E−10 0.309 0.308

EXAMPLE 10 Solubility of difluoromethane (HFC-32) in1-octyl-3-methylimidazolium iodide [omim][I]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided.

Table 11 provides data for C_(o), C_(s), D, X_(calc), and X_(meas) at atemperature of 25° C. TABLE 11 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.1007 0.01 0.06 1.75E−11 0.004 0.004 25.2 1.0021 0.23 0.80 1.77E−110.048 0.048 25.0 2.4971 1.20 2.13 1.86E−11 0.119 0.118 25.0 3.9999 2.583.55 2.27E−11 0.186 0.185 25.0 5.5008 4.07 5.04 3.13E−11 0.247 0.24625.0 6.9964 5.64 6.64 3.81E−11 0.306 0.306 25.0 8.5027 7.52 8.332.86E−11 0.360 0.362 25.0 10.0022 9.27 10.35 6.37E−11 0.417 0.416

EXAMPLE 11 Solubility of difluoromethane (HFC-32) in1,3-dioctylimidazolium iodide [doim][I]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided.

Table 12 provides data for C_(o), C_(s), D, X_(calc), and X_(meas) at atemperature of 25° C. TABLE 12 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.1002 0.03 0.11 1.78E−11 0.009 0.007 25.0 1.0010 0.29 0.87 2.11E−110.066 0.064 25.0 2.5003 1.29 2.17 2.35E−11 0.152 0.150 25.0 4.0024 2.623.51 2.91E−11 0.227 0.225 25.0 5.5024 4.03 4.93 3.54E−11 0.295 0.29325.0 7.0010 5.51 6.43 4.25E−11 0.357 0.355 24.9 8.4988 7.12 8.075.00E−11 0.415 0.413 25.0 10.0024 8.83 9.85 5.77E−11 0.469 0.468

EXAMPLE 12 Solubility of difluoromethane (HFC-32) in1-ethyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide[emim][BEI]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 13a, 13b, 13c and 13d provide data for C_(o), C_(s), D, X_(calc),and X_(meas) at a temperature of 10° C., 25° C., 50° C., and 75° C.,respectively. TABLE 13a C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (massD (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 10.0 0.1010.06 0.15 3.79E−11 0.014 0.014 10.0 1.000 1.06 1.78 4.78E−11 0.146 0.14410.0 2.495 3.58 4.83 7.37E−11 0.324 0.323 10.0 3.995 7.14 8.52 1.17E−100.468 0.467 10.0 5.496 11.75 13.23 1.51E−10 0.590 0.590 10.0 6.994 17.7619.75 1.72E−10 0.699 0.699 10.0 8.505 26.95 30.37 1.67E−10 0.805 0.799

TABLE 13b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.0 0.096 0.03 0.117.5E−11 0.010 0.010 25.0 0.997 0.71 1.22 7.9E−11 0.104 0.104 25.0 2.4962.49 3.19 1.1E−10 0.237 0.237 25.0 3.996 4.61 5.33 1.3E−10 0.347 0.34725.0 5.493 7.03 7.75 1.6E−10 0.443 0.442 25.0 6.993 9.70 10.49 1.8E−100.525 0.525 25.0 8.503 12.87 13.71 2.1E−10 0.600 0.598 25.0 10.005 16.4917.56 1.7E−10 0.668 0.666

TABLE 13c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.100 0.00 0.041.66E−10 0.004 0.004 50.0 0.997 0.49 0.65 1.34E−10 0.058 0.059 50.02.497 1.46 1.73 1.79E−10 0.142 0.145 50.0 3.996 2.61 2.83 1.92E−10 0.2160.219 50.0 5.495 3.82 3.98 2.19E−10 0.281 0.285 50.0 6.995 4.92 5.192.28E−10 0.341 0.345 50.0 8.504 6.20 6.46 2.73E−10 0.395 0.399 50.09.993 7.54 7.81 1.62E−10 0.444 0.449

TABLE 13d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.101 0.00 0.013.92E−10 0.001 0.001 74.9 1.000 0.32 0.41 2.60E−10 0.038 0.038 74.92.501 0.99 1.10 3.32E−10 0.095 0.095 74.9 3.992 1.72 1.79 3.96E−10 0.1470.146 74.9 5.496 2.39 2.49 3.53E−10 0.194 0.194 74.9 6.996 3.08 3.223.41E−10 0.239 0.239 74.9 8.504 3.87 3.96 3.48E−10 0.280 0.280 74.99.994 4.55 4.70 1.92E−10 0.318 0.317

EXAMPLE 13 Solubility of difluoromethane (HFC-32) in1,2-dimethyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide[dmpim][BMeI]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Table 14 provides data for C_(o), C_(s), D, X_(calc), and X_(meas) at atemperature of 25° C. TABLE 14 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.90.0989 0.02 0.11 6.31E−11 0.008 0.008 25.0 0.9951 0.65 1.22 6.60E−110.091 0.090 25.0 2.4949 2.44 3.25 8.94E−11 0.213 0.212 25.0 3.9762 4.625.46 1.21E−10 0.317 0.317 25.0 5.5013 7.08 8.00 1.46E−10 0.412 0.41225.0 7.0174 10.02 10.92 1.75E−10 0.497 0.496 25.0 8.5131 13.56 14.292.23E−10 0.573 0.573 25.0 10.0108 17.55 18.41 2.33E−10 0.645 0.645

EXAMPLE 14 Solubility of difluoromethane (HFC-32) in3-methyl-1-propylpyridinium bis(trifluoromethylsulfonyl)imide[pmpy][BMeI]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 15a, 15b, 15c, and 15d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 15a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)fraction) 10.0 0.1021 0.08 0.02 5.76E−11 0.002 0.015 10.0 1.0001 1.032.01 5.72E−11 0.141 0.140 10.0 2.4942 3.95 5.31 1.05E−10 0.310 0.31110.0 3.9963 7.78 9.35 1.28E−10 0.452 0.452 10.0 5.4935 12.68 14.052.89E−10 0.567 0.570 10.0 6.9960 18.73 20.79 2.01E−10 0.678 0.679 10.08.4951 27.80 30.88 2.71E−10 0.781 0.778

TABLE 15b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.0951 0.02 0.129.96E−11 0.010 0.010 24.9 1.0020 0.74 1.32 1.00E−10 0.097 0.096 24.92.5034 2.67 3.44 1.20E−10 0.222 0.221 24.9 3.9959 4.93 5.73 1.52E−100.327 0.328 24.9 5.4973 7.52 8.30 1.92E−10 0.420 0.419 24.9 6.9923 10.3511.16 2.20E−10 0.501 0.502 24.9 8.4965 13.61 14.48 2.41E−10 0.575 0.57524.9 10.0044 17.35 18.06 6.21E−10 0.638 0.639

TABLE 15c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1025 0.04 0.082.10E−10 0.007 0.007 50.0 1.0031 0.59 0.76 1.86E−10 0.058 0.058 50.02.4979 1.64 1.93 2.01E−10 0.136 0.137 50.0 4.0004 2.82 3.11 2.80E−100.205 0.206 50.0 5.4945 4.05 4.36 2.37E−10 0.268 0.270 50.0 6.9935 5.395.64 3.50E−10 0.323 0.326 50.0 8.5031 6.71 6.97 3.95E−10 0.375 0.37850.0 9.9939 8.06 8.44 2.30E−10 0.425 0.427

TABLE 15d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.1026 0.03 0.043.94E−10 0.003 0.003 74.9 1.0023 0.04 0.46 3.89E−10 0.036 0.037 74.92.5020 1.06 1.19 3.96E−10 0.088 0.089 74.9 4.0021 1.77 1.91 4.00E−100.135 0.138 74.9 5.4931 2.53 2.65 3.62E−10 0.179 0.183 74.9 7.0026 3.273.39 4.62E−10 0.219 0.223 74.9 8.4935 4.04 4.15 4.76E−10 0.257 0.26274.9 10.0019 4.76 4.91 5.48E−10 0.293 0.300

EXAMPLE 15 Solubility of trifluoromethane (HFC-23) in1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 20 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 16a, 16b, 16c, and 16d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 16a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)fraction) 9.4 0.0962 — — — — 0.000 9.4 0.5000 0.00 0.25 1.54E−11 0.0100.010 9.6 1.0979 — — — — 0.028 9.5 4.0003 1.56 3.05 1.54E−11 0.113 0.1139.4 7.0000 4.14 5.76 2.17E−11 0.199 0.198 9.5 9.9934 7.15 8.81 2.89E−110.282 0.281 9.5 12.9972 10.59 12.22 4.26E−11 0.361 0.361 9.5 14.996413.48 14.81 5.68E−11 0.414 0.414 10.0 20.0017 — — — — 0.528

TABLE 16b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.0991 — — — —0.000 24.9 0.4972 0.03 0.19 2.56E−11 0.008 0.008 24.9 0.9994 0.24 0.443.22E−11 0.018 0.018 24.9 3.9934 1.17 2.08 2.37E−11 0.080 0.079 24.96.9953 2.86 3.79 3.01E−11 0.138 0.137 24.9 10.0041 4.68 5.59 3.95E−110.194 0.193 24.9 13.0056 6.66 7.52 3.89E−11 0.248 0.247 25.0 15.00008.09 8.80 5.73E−11 0.281 0.281 24.9 19.9990 11.36 12.49 7.12E−11 0.3670.367

TABLE 16c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.0981 0.00 0.016.34E−11 0.000 0.000 50.0 0.4984 0.03 0.11 6.26E−11 0.005 0.005 50.00.9961 0.17 0.27 7.35E−11 0.011 0.011 50.0 3.9965 0.89 1.27 5.88E−110.049 0.049 50.0 7.0036 1.90 2.25 6.74E−11 0.085 0.085 50.0 10.0041 2.923.27 8.02E−11 0.121 0.120 50.0 12.9931 3.95 4.29 7.47E−11 0.154 0.15450.0 15.0015 4.69 5.01 1.16E−10 0.176 0.176 50.0 19.9932 6.41 6.781.08E−10 0.228 0.227

TABLE 16d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.0965 — — — —0.001 74.9 0.4973 0.03 0.08 8.13E−11 0.003 0.003 74.9 0.9975 0.12 0.211.22E−10 0.008 0.008 74.9 3.9971 0.63 0.84 1.04E−10 0.033 0.033 74.97.0016 1.45 1.42 2.86E−12 0.055 0.057 75.0 9.9934 1.92 2.08 1.08E−100.079 0.080 74.9 13.0031 2.55 2.72 2.23E−10 0.102 0.103 74.9 14.99432.98 3.17 1.09E−10 0.117 0.118 74.9 19.9998 4.00 4.22 2.31E−10 0.1520.146

EXAMPLE 16 Solubility of trifluoromethane (HFC-23) in1-ethyl-3-methylimidazolium hexafluorophosphate [emim][PF₆]

A solubility and diffusivity study was made at a temperature of 60, and75° C. over a pressure range from 0 to 20 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided.

Tables 17a, and 17b provide data for C_(o), C_(s), D, X_(calc), andX_(meas) at a temperature of 60° C., and 75° C., respectively. TABLE 17aC_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol. (° C.)(bar) %) %) (m²/sec) fraction) fraction) 59.9 0.0992 — — — — 0.000 59.90.4997 0.03 0.09 1.23E−10 0.003 0.003 59.9 0.9973 0.13 0.20 1.28E−100.007 0.007 59.9 4.0026 0.76 0.86 1.21E−10 0.031 0.030 59.9 6.9974 1.301.50 1.58E−10 0.053 0.053 59.9 10.0001 2.02 2.18 1.12E−10 0.075 0.07660.0 12.9920 2.71 2.86 2.55E−10 0.097 0.098 59.9 15.0002 3.20 3.351.68E−10 0.113 0.113 59.9 19.9990 4.39 4.54 3.12E−10 0.148 0.151

TABLE 17b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.0965 0.02 0.021.12E−10 0.001 0.001 74.9 0.4982 — — — — 0.002 74.9 0.9998 0.12 0.161.94E−10 0.006 0.006 74.9 4.0035 0.56 0.65 2.18E−10 0.023 0.024 74.96.9933 1.06 1.14 1.17E−10 0.040 0.040 74.9 10.0041 1.56 1.65 2.73E−100.058 0.057 75.0 12.9969 2.00 2.16 1.02E−10 0.075 0.074 74.9 15.00412.47 2.49 7.22E−10 0.085 0.083 75.0 19.9939 — — — — 0.116

EXAMPLE 17 Solubility of difluoromethane (HFC-32) in1-ethyl-3-methylimidazolium bis(trifluoroethylsulfonyl)imide[emim][BMeI]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 18a, 18b, 18c, and 18d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 18a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)fraction) 10.0 0.1015 0.11 0.19 6.94E−11 0.014 0.014 10.0 1.0012 1.122.06 8.72E−11 0.137 0.136 10.0 2.5030 4.25 5.55 1.18E−10 0.306 0.30510.0 3.9929 8.20 9.58 1.50E−10 0.444 0.446 10.0 5.4925 13.38 14.831.78E−10 0.567 0.567 10.0 7.0043 19.75 21.63 2.36E−10 0.675 0.668 10.08.4935 27.92 31.92 1.24E−10 0.779 0.785

TABLE 18b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.0 0.0959 0.09 0.138.36E−11 0.010 0.010 25.0 0.9981 0.86 1.38 1.22E−10 0.095 0.095 25.02.5024 2.88 3.56 1.61E−10 0.217 0.217 25.0 3.9937 5.27 5.97 1.56E−100.323 0.323 25.0 5.4940 7.90 8.60 2.00E−10 0.414 0.414 25.0 6.9946 10.7711.53 2.33E−10 0.495 0.495 25.0 8.4952 14.06 14.80 3.24E−10 0.566 0.56525.0 9.9967 17.74 18.58 3.20E−10 0.632 0.637

TABLE 18c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1022 0.04 0.073.03E−10 0.005 0.005 50.0 1.0029 0.55 0.77 2.18E−10 0.055 0.055 50.02.4972 1.71 1.98 2.19E−10 0.132 0.132 50.0 4.0011 2.95 3.21 2.86E−100.199 0.199 50.0 5.4949 4.22 4.50 2.47E−10 0.261 0.262 50.0 7.0033 5.525.80 3.97E−10 0.316 0.316 50.0 8.5044 6.93 7.20 2.90E−10 0.368 0.36450.0 10.0038 8.22 8.51 3.43E−10 0.411 0.412

TABLE 18d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D (mol. (mol.(° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.1028 0.01 0.036.36E−10 0.002 0.002 74.9 0.9981 0.36 0.46 3.41E−10 0.034 0.034 74.92.4971 1.09 1.21 4.21E−10 0.084 0.084 74.9 3.9948 1.82 1.96 5.11E−100.130 0.130 74.9 5.5026 2.60 2.71 5.24E−10 0.173 0.173 74.9 6.9919 3.373.49 3.22E−10 0.213 0.213 74.9 8.5039 4.16 4.28 4.63E−10 0.252 0.25174.9 10.0045 5.10 5.10 4.75E−09 0.288 0.284

EXAMPLE 18 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide[bmpy][BMeI]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 19. TABLE 19 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0961 0.04 0.12 6.81E−11 0.010 0.010 25.0 0.9950 0.66 1.32 7.82E−110.097 0.100 25.0 2.4949 2.58 3.38 1.21E−10 0.219 0.223 25.0 3.9948 4.765.59 1.49E−10 0.321 0.329 25.0 5.4962 7.25 8.10 1.53E−10 0.414 0.42425.0 7.0055 — — — — 0.505 25.0 8.5057 13.03 14.47 1.15E−11 0.575 0.58025.0 10.0002 17.06 18.28 2.31E−10 0.642 0.648

EXAMPLE 19 Solubility of difluoromethane (HFC-32) in1-ethyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[emim][TFES]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 20. TABLE 20 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0987 0.01 0.10 4.12E−11 0.006 0.006 24.9 0.9910 0.40 1.03 3.25E−110.055 0.054 24.9 2.4841 2.48 2.65 2.94E−11 0.133 0.132 24.9 3.9945 3.664.45 4.93E−11 0.207 0.207 24.9 5.4957 5.78 6.37 5.92E−11 0.276 0.27724.9 7.0221 — — — — 0.344 24.9 8.4832 9.79 10.90 1.04E−10 0.407 0.40724.9 10.0160 12.55 13.66 1.21E−10 0.470 0.471

EXAMPLE 20 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[bmim][TFES]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 21. TABLE 21 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0967 0.02 0.12 2.37E−11 0.007 0.007 25.0 0.9986 0.99 1.29 1.47E−110.075 0.072 25.0 2.4997 2.19 3.31 2.67E−11 0.174 0.171 25.0 3.9716 4.335.40 3.95E−11 0.260 0.261 25.0 5.4838 6.84 7.78 4.76E−11 0.342 0.34225.0 6.9946 8.98 10.39 7.75E−11 0.416 0.416 25.0 8.4811 11.98 13.278.73E−11 0.485 0.485 25.0 9.9886 15.07 16.62 1.35E−10 0.551 0.550

EXAMPLE 21 Solubility of difluoromethane (HFC-32) in1-dodecyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[dmim][TFES]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 22. TABLE 22 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0963 0.00 0.06 5.01E−11 0.005 0.006 25.0 0.9950 0.35 0.95 4.72E−110.072 0.074 25.0 2.5100 1.63 2.56 5.06E−11 0.175 0.178 25.0 3.9971 4.154.30 3.01E−11 0.266 0.271 25.0 5.4807 6.06 6.16 4.74E−11 0.346 0.35325.0 7.0007 7.98 8.29 6.81E−11 0.421 0.429 25.0 8.5003 10.50 10.668.17E−11 0.490 0.497 25.0 10.0101 12.09 13.39 1.25E−10 0.555 0.562

EXAMPLE 22 Solubility of difluoromethane (HFC-32) in1-heptyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate[hmim][TFES]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 23. TABLE 23 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0988 0.01 0.11 3.86E−11 0.008 0.008 25.0 1.0023 0.47 1.25 3.87E−110.081 0.081 25.0 2.5100 2.18 3.30 4.35E−11 0.192 0.190 25.0 3.9884 4.395.44 5.84E−11 0.286 0.286 25.0 5.4973 7.25 7.82 6.41E−11 0.371 0.37125.0 6.9871 9.99 10.43 9.01E−11 0.448 0.448 25.0 8.4785 12.28 13.401.30E−10 0.518 0.518 25.0 9.9795 15.45 16.83 1.56E−10 0.585 0.586

EXAMPLE 23 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium acetate [bmim][Ac]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 24. TABLE 24 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.10.0985 0.09 0.25 2.19E−11 0.010 0.010 25.0 0.9968 0.72 2.17 2.64E−110.078 0.077 25.0 2.4979 3.25 5.30 4.05E−11 0.176 0.174 25.0 4.0040 6.598.59 5.64E−11 0.264 0.258 25.0 5.4984 9.83 11.70 1.02E−10 0.335 0.33325.0 6.9974 13.24 15.00 1.46E−10 0.402 0.397 24.9 8.5016 16.74 18.361.83E−10 0.462 0.456 25.0 10.0044 20.30 21.89 2.10E−10 0.516 0.511

EXAMPLE 24 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium2-(1,2,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate[bmim][FS]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 25. TABLE 25 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0999 0.02 0.11 4.30E−11 0.009 0.009 25.0 0.9966 0.82 1.20 4.29E−110.092 0.092 25.0 2.5009 2.29 3.17 5.44E−11 0.215 0.213 25.0 4.0040 4.165.26 9.11E−11 0.318 0.317 25.0 5.4999 6.53 7.68 1.04E−10 0.411 0.41125.0 6.9963 9.19 10.36 1.49E−10 0.492 0.493 25.0 8.4944 12.24 13.241.26E−09 0.561 0.565 25.0 10.0048 15.74 17.00 2.78E−10 0.632 0.632

EXAMPLE 25 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium 1,1,2,3,3,3-hexafluoropropanesulfonate[bmim][HFPS]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 26. TABLE 26 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0945 0.02 0.11 3.33E−11 0.010 0.010 25.0 0.9999 0.56 1.25 3.17E−110.106 0.104 25.0 2.4976 2.29 3.29 3.90E−11 0.242 0.241 25.0 3.9945 4.345.40 6.98E−11 0.349 0.347 25.0 5.4949 6.56 7.79 6.98E−11 0.443 0.44325.0 6.9975 9.29 10.45 1.11E−10 0.523 0.523 25.0 8.4943 12.16 13.601.04E−10 0.597 0.599 25.0 10.0042 15.98 17.43 1.67E−10 0.665 0.664

EXAMPLE 26 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium methyl sulfonate [bmim][MeSO₄]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 27. TABLE 27 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0993 0.12 0.24 2.08E−11 0.012 0.012 25.0 1.0010 0.53 1.48 2.67E−110.068 0.068 25.0 2.4982 2.15 3.65 3.04E−11 0.154 0.155 25.0 3.9954 4.415.87 4.15E−11 0.231 0.232 25.1 5.5009 6.87 8.16 5.23E−11 0.299 0.30225.0 6.9953 9.24 10.77 6.24E−11 0.367 0.369 25.0 8.5005 11.97 13.339.89E−11 0.425 0.427 25.0 10.0059 14.75 16.32 1.20E−10 0.484 0.482

EXAMPLE 27 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium thiocyanate [bmim][SCN]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 28. TABLE 28 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0947 0.02 0.10 8.08E−11 0.004 0.004 25.0 1.0031 0.45 1.11 8.57E−110.041 0.041 25.0 2.5033 1.90 2.84 1.03E−10 0.100 0.099 25.0 3.9958 3.664.68 1.11E−10 0.157 0.156 25.0 5.4999 — — — — 0.212 25.0 6.9966 7.628.73 1.42E−10 0.266 0.267 25.0 8.4947 9.93 11.01 1.83E−10 0.319 0.32025.0 9.9919 12.30 13.55 2.05E−10 0.373 0.373

EXAMPLE 28 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 29. TABLE 29 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0951 0.02 0.12 4.46E−11 0.010 0.010 25.0 1.0007 0.58 1.35 5.27E−110.103 0.102 25.0 2.4964 2.43 3.56 6.70E−11 0.236 0.236 25.0 3.9947 4.815.94 9.64E−11 0.346 0.346 25.0 5.4938 7.52 8.62 1.20E−10 0.442 0.44225.0 6.9941 10.49 11.65 1.49E−10 0.525 0.525 25.0 8.4946 13.93 15.151.78E−10 0.600 0.599 25.0 9.9937 18.00 19.36 2.06E−10 0.668 0.668

EXAMPLE 29 Solubility of difluoromethane (HFC-32) in1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES]

A solubility and diffusivity study was made at a temperature of 25° C.over a pressure range from 0 to 10 bar where the solubilities(X_(meas.)) were measured using a gravimetric microbalance and thediffusivities (D) were calculated using a one-dimensional diffusionmodel analysis. The initial concentration (C_(o)), final saturationconcentration (C_(s)), and calculated solubility (X_(calc.)) are alsoprovided in Table 30. TABLE 30 C_(o) C_(s) X_(calc.) X_(meas.) T P (mass(mass D (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 25.00.0947 0.02 0.13 4.26E−11 0.010 0.010 25.0 1.0031 0.57 1.42 4.51E−110.097 0.096 25.0 2.5033 2.40 3.71 5.83E−11 0.222 0.222 25.0 3.9958 4.926.28 7.11E−11 0.332 0.332 25.0 5.4999 7.79 9.04 9.96E−11 0.425 0.42425.0 6.9966 10.71 12.12 1.23E−10 0.506 0.506 25.0 8.4947 14.21 15.631.59E−10 0.579 0.578 25.0 9.9919 18.20 19.62 2.51E−10 0.644 0.644

EXAMPLE 30 Solubility of 1,1,1,2-tetrafluoroethane (HFC-134a) in1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(trifluoromethoxy)ethanesulfonate [bmim][TTES]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 18a, 18b, 18c, and 18d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 31a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)fraction) 10.0 0.1025 0.08 0.66 1.04E−11 0.025 0.026 10.0 0.5002 0.973.29 1.25E−11 0.114 0.117 10.0 1.0027 4.03 7.05 1.62E−11 0.223 0.22510.0 1.5018 7.93 11.31 2.16E−11 0.326 0.326 9.9 2.0022 12.23 16.253.26E−11 0.424 0.424 10.0 2.5048 17.58 22.11 5.31E−11 0.518 0.514 10.02.9946 23.87 30.15 5.28E−11 0.620 0.628 10.0 3.5047 36.32 44.43 7.71E−110.752 0.745

TABLE 31b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.1018 1.510.35 1.19E−11 0.013 0.017 24.9 0.5032 0.77 2.07 2.17E−11 0.074 0.07525.1 1.0024 2.52 4.22 2.60E−11 0.143 0.143 24.8 1.5015 4.77 6.523.00E−11 0.209 0.208 25.0 2.0032 7.17 9.00 3.27E−11 0.272 0.271 25.02.5035 9.59 11.56 4.43E−11 0.331 0.331 24.9 3.0013 12.31 14.44 5.05E−110.390 0.389 24.8 3.5010 15.87 17.69 4.50E−11 0.449 0.450

TABLE 31c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1048 0.170.25 5.76E−11 0.009 0.009 50.0 0.5031 0.47 1.06 5.35E−11 0.039 0.03950.0 1.0023 1.37 2.11 5.79E−11 0.076 0.076 50.0 1.5021 2.43 3.196.35E−11 0.111 0.111 50.0 2.0026 3.50 4.28 6.64E−11 0.145 0.145 50.02.5033 4.67 5.41 6.97E−11 0.178 0.179 50.0 3.0035 5.81 6.58 7.24E−110.211 0.211 50.0 3.5016 7.22 7.78 6.89E−11 0.242 0.243

TABLE 31d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.1031 0.060.13 1.04E−10 0.005 0.005 74.9 0.5054 0.31 0.62 1.18E−10 0.023 0.02374.9 1.0049 0.85 1.23 1.22E−10 0.045 0.045 74.9 1.5029 1.49 1.851.21E−10 0.067 0.067 74.9 2.0041 2.10 2.46 1.25E−10 0.087 0.087 74.92.5042 2.71 3.08 1.26E−10 0.107 0.108 74.9 3.0024 3.33 3.72 1.38E−100.128 0.128 74.9 3.5039 4.19 4.36 1.09E−10 0.147 0.147

EXAMPLE 31

Solubility of 1,1,1,2-tetrafluoroethane (HFC-134a) in1-butyl-3-methylimidazolium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [bmim][TPES]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 32a, 32b, 32c, and 32d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 32a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)fraction) 10.0 0.1024 0.06 0.66 9.33E−12 0.028 0.028 10.0 0.5038 1.013.39 1.15E−11 0.131 0.132 10.0 1.0043 4.05 7.26 1.71E−11 0.251 0.253 9.91.5033 8.17 11.65 2.53E−11 0.361 0.362 10.0 2.0022 12.78 16.90 3.67E−110.465 0.464 10.0 2.5024 18.33 23.30 5.37E−11 0.565 0.566 10.0 3.004125.90 32.36 7.06E−11 0.672 0.670 9.9 3.5039 38.42 47.48 6.49E−11 0.7940.796

TABLE 32b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.1026 0.110.45 1.80E−11 0.019 0.018 24.9 0.5031 0.72 2.09 2.32E−11 0.084 0.08424.9 1.0018 2.62 4.33 2.59E−11 0.162 0.162 24.9 1.5015 4.92 6.703.23E−11 0.235 0.235 24.9 2.0029 7.33 9.23 4.14E−11 0.303 0.303 24.92.5038 9.92 11.93 4.99E−11 0.367 0.366 24.9 3.0034 12.73 14.93 5.74E−110.429 0.428 24.9 3.5012 16.44 18.40 4.94E−11 0.491 0.490

TABLE 32c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1036 0.200.26 8.37E−11 0.011 0.011 50.0 0.5032 0.47 1.10 5.99E−11 0.045 0.04550.0 1.0023 1.52 2.20 5.66E−11 0.088 0.087 50.0 1.5021 2.55 3.326.59E−11 0.128 0.128 50.0 2.0025 3.69 4.47 6.87E−11 0.167 0.167 50.02.5035 4.90 5.66 7.37E−11 0.204 0.204 50.0 3.0042 6.08 6.87 8.56E−110.240 0.240 50.0 3.5035 7.49 8.10 8.02E−11 0.274 0.274

TABLE 32d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.1051 0.110.15 1.09E−10 0.006 0.006 74.9 0.5052 0.34 0.65 1.19E−10 0.027 0.02774.9 1.0054 0.92 1.29 1.22E−10 0.053 0.053 75.0 1.5046 1.90 1.931.93E−09 0.078 0.078 74.7 2.0056 2.25 2.59 1.05E−10 0.102 0.102 74.92.5053 2.88 3.22 1.50E−10 0.124 0.125 74.9 3.0041 3.56 3.90 1.30E−100.148 0.148 74.9 3.5051 4.34 4.56 1.42E−10 0.170 0.170

EXAMPLE 32 Solubility of 1,1,1,2-tetrafluoroethane (HFC-134a) in1-ethyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide[emim][BEI]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 33a, 33b, 33c, and 33d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 33a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)fraction) 10.0 0.1031 0.09 0.61 1.92E−11 0.029 0.024 10.0 0.5039 1.212.51 4.25E−07 0.110 0.120 10.0 1.0027 4.05 6.65 2.95E−11 0.255 0.23910.0 1.5024 7.74 10.72 3.68E−11 0.366 0.354 10.0 2.0011 12.01 15.614.88E−11 0.471 0.464 10.0 2.5009 17.79 21.74 6.58E−11 0.572 0.569 10.03.0043 24.67 30.25 8.67E−11 0.676 0.668 10.0 3.5049 37.47 44.30 6.14E−110.793 0.793

TABLE 33b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.1054 0.210.42 2.60E−11 0.020 0.019 24.9 0.5052 0.82 1.92 3.76E−11 0.086 0.08624.9 1.0046 2.55 3.90 4.22E−11 0.163 0.163 24.9 1.5040 4.69 6.024.77E−11 0.236 0.235 24.9 2.0037 6.73 8.29 5.70E−11 0.303 0.304 24.92.5031 9.15 10.79 6.65E−11 0.368 0.368 24.9 3.0043 11.73 13.53 7.90E−110.430 0.429 24.9 3.5054 15.15 16.56 7.29E−11 0.489 0.488

TABLE 33c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1046 0.140.23 5.84E−11 0.011 0.011 50.0 0.5050 0.58 1.00 6.72E−11 0.046 0.04650.0 1.0043 1.42 1.99 8.15E−11 0.089 0.089 50.0 1.5046 2.48 3.007.67E−11 0.130 0.130 50.0 2.0037 3.46 4.04 8.44E−11 0.168 0.168 50.02.5033 4.51 5.10 8.82E−11 0.205 0.205 50.0 3.0034 5.57 6.19 9.36E−110.241 0.241 50.0 3.5040 6.98 7.32 8.24E−11 0.275 0.276

TABLE 33d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.1044 0.100.13 1.30E−10 0.006 0.006 74.9 0.5057 0.37 0.58 1.36E−10 0.027 0.02774.9 1.0042 0.87 1.16 1.35E−10 0.053 0.053 74.9 1.5043 1.48 1.731.32E−10 0.078 0.078 74.9 2.0041 2.01 2.30 1.49E−10 0.102 0.102 74.92.4957 2.60 2.88 1.42E−10 0.125 0.125 74.9 3.0049 3.22 3.47 1.69E−100.148 0.147 74.9 3.5027 3.89 4.06 1.17E−10 0.169 0.169

EXAMPLE 33 Solubility of 1,1,1,2-tetrafluoroethane (HFC-134a) in1-butyl-3-methylimidazolium 1,1,2,3,3-hexafluoropropanesulfonate[bmim][HFPS]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 34a, 34b, 34c, and 34d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 34a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)fraction) 10.0 0.0993 0.00 0.41 1.09E−11 0.015 0.015 9.9 0.5012 0.622.43 8.91E−12 0.083 0.082 10.0 1.0001 2.78 5.36 1.13E−11 0.170 0.17210.0 1.4989 5.94 8.89 1.38E−11 0.261 0.264 9.9 1.9997 9.63 12.822.42E−11 0.348 0.350 10.0 2.4950 13.70 18.23 2.42E−11 0.447 0.447 10.03.0010 19.60 24.78 4.81E−11 0.545 0.550 10.1 3.4937 27.72 36.37 7.13E−110.675 0.677

TABLE 34b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 24.9 0.1007 −0.020.26 1.61E−11 0.009 0.011 24.9 0.5000 0.50 1.75 2.46E−11 0.061 0.05524.9 1.0002 1.80 3.22 1.51E−10 0.108 0.109 24.9 1.4995 3.60 5.071.50E−11 0.162 0.163 24.9 1.9931 5.36 7.12 1.78E−11 0.218 0.220 25.02.5041 7.52 9.10 2.66E−11 0.267 0.269 24.9 3.0042 9.65 11.44 2.46E−110.319 0.322 24.9 3.5020 12.23 13.92 3.10E−11 0.370 0.374

TABLE 34c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1007 0.010.16 3.94E−11 0.006 0.006 50.0 0.5006 0.28 0.81 3.51E−11 0.029 0.02950.0 0.9997 1.11 1.69 2.84E−11 0.059 0.059 50.0 1.4987 1.93 2.583.30E−11 0.088 0.088 50.0 1.9941 2.87 3.53 2.73E−11 0.117 0.118 50.02.5040 3.73 4.42 4.20E−11 0.144 0.145 50.0 2.9997 4.65 5.37 4.79E−110.171 0.172 50.0 3.5040 5.64 6.32 4.79E−11 0.197 0.198

TABLE 34d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.0989 0.040.10 5.08E−11 0.003 0.004 74.9 0.5015 0.21 0.46 2.62E−10 0.016 0.01874.9 1.0009 0.69 1.01 6.65E−11 0.036 0.036 74.9 1.5002 1.17 1.517.55E−11 0.053 0.053 74.9 2.0006 1.67 2.03 6.73E−11 0.070 0.070 74.92.4996 2.18 2.53 8.11E−11 0.086 0.087 74.9 3.0020 2.70 3.06 8.14E−110.103 0.104

EXAMPLE 34 Solubility of 1,1,1,2-tetrafluoroethane (HFC-134a) intetradecyl(trihexyl) phosphonium1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate [6,6,6,14-P][TPES]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 35a, 35b, 35c, and 35d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 35a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)Fraction) 10.0 0.0993 0.10 0.52 1.65E−11 0.038 0.038 9.7 0.5001 0.872.99 2.04E−11 0.190 0.190 9.9 1.0005 3.55 6.26 2.72E−11 0.338 0.338 9.81.4988 7.01 9.95 3.28E−11 0.458 0.452 10.1 1.9940 10.46 13.72 5.63E−110.549 0.551 9.8 2.4956 14.69 18.30 1.01E−10 0.631 0.634 9.7 2.9998 19.7824.52 1.23E−10 0.713 0.718 9.6 3.4947 26.93 34.29 2.24E−10 0.800 0.799

TABLE 35b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) Fraction) 24.9 0.1000 −0.010.26 2.82E−11 0.019 0.018 24.9 0.5002 0.50 1.75 4.18E−11 0.120 0.12125.0 0.9998 2.14 3.73 4.58E−11 0.229 0.228 24.9 1.4991 4.13 5.795.46E−11 0.320 0.320 24.9 2.0001 6.22 7.90 6.55E−11 0.396 0.397 24.92.5034 8.35 10.05 8.92E−11 0.461 0.462 24.9 3.0041 10.54 12.31 9.57E−110.518 0.520 24.9 3.5040 12.92 14.84 1.11E−10 0.571 0.574

TABLE 35c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1013 0.210.09 1.08E−11 0.007 0.011 50.0 0.5011 0.34 0.94 9.52E−11 0.068 0.06850.0 1.0012 1.24 1.97 9.91E−11 0.133 0.134 50.0 1.4996 2.29 3.011.07E−10 0.192 0.193 50.0 2.0006 3.37 4.07 9.79E−11 0.245 0.246 50.02.5005 4.37 5.10 1.22E−10 0.291 0.294 50.0 2.9997 5.44 6.19 1.19E−100.335 0.339 50.1 3.4970 6.68 7.33 1.14E−10 0.377 0.381

TABLE 35d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 74.9 0.1011 0.000.03 1.84E−10 0.002 0.003 74.9 0.5019 0.22 0.52 1.81E−10 0.039 0.03974.9 1.0009 0.77 1.16 1.97E−10 0.082 0.083 74.9 1.4959 1.41 1.772.08E−10 0.121 0.122 74.9 2.0012 2.03 2.40 2.27E−10 0.158 0.160 74.92.5033 2.65 3.03 2.28E−10 0.193 0.194 74.9 3.0034 3.30 3.65 2.05E−100.225 0.227 74.9 3.5051 3.96 4.27 2.13E−10 0.254 0.256

EXAMPLE 35 Solubility of 1,1,1,2-tetrafluoroethane (HFC-134a) intributyl(tetradecyl)phosphonium 1,1,2,3,3,3-hexafluoropropanesulfonate[4,4,4,14-P][HFPS]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 10 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 36a, 36b, 36c, and 36d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 36a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)Fraction) 10.2 0.0991 0.08 0.49 2.23E−11 0.029 0.032 9.9 0.5001 0.722.95 1.30E−11 0.158 0.152 10.2 0.9998 3.17 6.30 1.74E−11 0.293 0.28910.0 1.4999 6.59 9.78 2.67E−11 0.401 0.403 10.0 1.9996 10.48 13.804.77E−11 0.497 0.494 10.0 2.5034 14.41 18.75 5.41E−11 0.587 0.587 10.03.0020 19.66 24.79 1.49E−10 0.670 0.672 10.1 3.4928 27.70 34.01 2.02E−100.761 0.763

TABLE 36b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) Fraction) 25.0 0.0998 0.050.34 1.70E−11 0.021 0.019 24.9 0.5001 0.50 1.83 2.56E−11 0.103 0.10424.9 0.9994 2.11 3.76 3.19E−11 0.194 0.194 25.0 1.4988 4.06 5.793.71E−11 0.275 0.273 24.9 2.0017 6.03 8.06 3.60E−11 0.351 0.350 25.02.5003 8.43 10.48 4.88E−11 0.419 0.418 25.0 2.9990 10.82 12.84 7.38E−110.476 0.478 25.0 3.5021 13.55 15.47 1.01E−10 0.530 0.530

TABLE 36c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.0 0.1009 0.000.17 6.85E−11 0.010 0.010 50.0 0.5001 0.32 0.96 6.65E−11 0.056 0.05650.0 0.9994 1.20 1.99 6.73E−11 0.111 0.110 50.0 1.4992 2.24 3.046.51E−11 0.162 0.161 50.0 2.0003 3.31 4.09 7.46E−11 0.208 0.209 50.02.4945 4.29 5.16 8.18E−11 0.251 0.254 50.0 2.9994 5.46 6.22 1.11E−100.290 0.293 50.0 3.4964 7.54 8.32 7.36E−11 0.359 0.333

TABLE 36d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.1006 0.080.14 1.36E−10 0.009 0.009 74.9 0.5041 0.30 0.63 1.39E−10 0.037 0.03774.9 1.0014 0.83 1.25 1.37E−10 0.072 0.072 74.9 1.5002 1.47 1.871.43E−10 0.105 0.105 74.9 2.0014 2.07 2.47 1.63E−10 0.135 0.136 74.92.5044 2.66 3.08 1.70E−10 0.164 0.165 74.9 3.0037 2.75 3.15 1.51E−100.167 0.194 74.9 3.5039 3.44 3.79 1.70E−10 0.196 0.221

EXAMPLE 36

The description of the microbalance components, shown in FIG. 18, areprovided below. TABLE 37 Microbalance Components Contributing toBuoyancy Calculation Weight Density Temperature Subscript Item (g)Material (g · cm⁻³) (° C.) s Dry sample m_(s) [bmim][PF₆] ρ_(s) SampleTemp. [bmim][BF₄] (T_(s)) a Interacted gas m_(a) CO₂ ρ_(a) (T_(s)) i₁Sample container 0.5986 Pyrex 2.23 (T_(s)) i₂ Wire 0.051 Tungsten 21.0(T_(s)) i₃ Chain 0.3205 Gold 19.3 30 j₁ Counter-weight 0.8054 StainlessSteel 7.9 25 j₂ Hook 0.00582 Tungsten 21.0 25 j₃ Chain 0.2407 Gold 19.330

EXAMPLE 37 Solubility of carbon dioxide (CO₂) in1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF₆]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 20 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 38a, 38b, 38c, and 38d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 38a C_(o) C_(s) X_(calc.) X_(meas.) T P(mass (mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)Fraction) 9.9 0.097 0.00 0.07 1.5E−11 0.006 0.004 9.9 0.501 0.10 0.242.0E−11 0.017 0.016 9.9 1.002 0.29 0.46 2.2E−11 0.030 0.029 10.4 3.9960.85 1.72 2.6E−11 0.101 0.102 10.6 6.996 2.15 2.97 3.0E−11 0.165 0.16510.5 10.000 3.43 4.22 3.6E−11 0.221 0.220 8.9 13.003 4.95 5.69 — 0.2800.278 9.9 14.998 5.84 6.35 7.4E−11 0.306 0.302 9.9 19.998 7.51 8.355.2E−11 0.375 0.367

TABLE 38b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) Fraction) 24.9 0.102 0.000.01 — 0.006 0.000 24.9 0.502 0.03 0.14 5.1E−11 0.011 0.009 24.9 1.0020.16 0.29 4.8E−11 0.020 0.018 25.0 3.996 0.65 1.19 4.5E−11 0.072 0.07125.0 7.000 1.55 2.07 5.4E−11 0.122 0.120 24.9 9.994 2.45 2.95 5.7E−110.167 0.164 24.9 12.999 3.31 3.80 6.8E−11 0.208 0.203 24.9 14.994 4.054.41 7.7E−11 0.238 0.227 24.9 19.992 5.19 5.80 8.1E−11 0.285 0.282

TABLE 38c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.1 0.102 0.010.03 11.3E−11 0.002 0.002 50.0 0.503 0.04 0.09 10.8E−11 0.006 0.006 50.01.002 0.12 0.19  9.7E−11 0.012 0.012 50.1 3.996 0.50 0.76 10.1E−11 0.0470.047 50.0 7.000 1.07 1.29 10.1E−11 0.078 0.078 50.0 9.998 1.59 1.8112.6E−11 0.107 0.107 50.0 13.002 2.13 2.34 12.7E−11 0.134 0.133 50.115.003 2.53 2.70 13.5E−11 0.152 0.151 50.0 19.998 3.27 3.56 14.8E−110.192 0.191

TABLE 38d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.102 0.010.02  9.5E−11 0.001 0.001 74.9 0.501 0.02 0.04 23.5E−11 0.002 0.002 74.91.000 0.07 0.11 21.3E−11 0.007 0.007 74.9 3.997 0.40 0.51 27.5E−11 0.0320.032 74.9 7.000 0.78 0.89 23.7E−11 0.055 0.055 74.8 10.002 1.18 1.2813.2E−11 0.077 0.077 75.0 13.003 1.50 1.64 69.5E−11 0.097 0.096 74.914.999 1.75 1.88 58.5E−11 0.110 0.110 75.1 19.995 2.36 2.45 28.4E−110.140 0.144

EXAMPLE 38 Solubility of carbon dioxide (CO₂) in1-butyl-3-methylimidazolium tetrafluoroborate [bmim][BF₄]

A solubility and diffusivity study was made at a temperature of 10, 25,50, and 75° C. over a pressure range from 0 to 20 bar where thesolubilities (X_(meas.)) were measured using a gravimetric microbalanceand the diffusivities (D) were calculated using a one-dimensionaldiffusion model analysis. The initial concentration (C_(o)), finalsaturation concentration (C_(s)), and calculated solubility (X_(calc.))are also provided.

Tables 39a, 39b, 39c, and 39d provide data for C_(o), C_(s), D,X_(calc), and X_(meas) at a temperature of 10° C., 25° C., 50° C., and75° C., respectively. TABLE 39a C_(o) C_(s) Xcalc. Xmeas. T P (mass(mass D_(eff.) (mol. (mol. (° C.) (bar) %) %) (m²/sec) fraction)Fraction) 9.6 0.102 0.00 0.04 4.0E−11 0.002 0.002 9.8 0.502 0.07 0.243.4E−11 0.013 0.013 9.9 1.001 0.26 0.46 4.8E−11 0.023 0.023 9.9 4.0010.97 1.88 3.8E−11 0.090 0.090 10.1 6.996 2.40 3.25 4.5E−11 0.147 0.1479.9 9.997 3.69 4.64 5.5E−11 0.202 0.202 9.9 13.002 5.12 5.93 6.9E−110.249 0.259 10.0 15.001 6.28 6.79 6.7E−11 0.278 0.288 9.9 20.002 7.898.97 8.0E−11 0.346 0.353

TABLE 39b C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) Fraction) 24.8 0.097 — — — —0.002 25.0 0.500 0.08 0.19 6.6E−11 0.011 0.010 24.9 1.001 0.23 0.367.3E−11 0.020 0.018 25.0 3.996 0.81 1.42 6.4E−11 0.069 0.068 25.0 7.0021.87 2.45 7.1E−11 0.116 0.114 24.8 9.997 2.88 3.46 7.7E−11 0.158 0.15625.0 13.002 3.88 4.44 9.3E−11 0.197 0.192 24.8 15.001 4.71 5.09 8.2E−110.222 0.216 24.9 20.002 6.03 6.66 10.0E−11  0.277 0.268

TABLE 39c C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 50.1 0.102 0.020.06 20.7E−11 0.003 0.003 50.0 0.501 0.08 0.13 24.8E−11 0.006 0.006 50.01.001 0.18 0.23 12.2E−11 0.012 0.012 50.0 3.997 0.62 0.88 15.5E−11 0.0430.043 50.0 6.996 1.23 1.49 17.4E−11 0.072 0.072 50.0 10.002 1.88 2.0914.2E−11 0.099 0.099 50.0 12.997 2.48 2.69 12.9E−11 0.124 0.124 50.015.001 2.94 3.07 17.4E−11 0.140 0.140 50.0 20.000 3.82 4.02 14.5E−110.177 0.176

TABLE 39d C_(o) C_(s) X_(calc.) X_(meas.) T P (mass (mass D_(eff.) (mol.(mol. (° C.) (bar) %) %) (m²/sec) fraction) fraction) 75.0 0.102 0.020.04 32.8E−11 0.002 0.002 75.0 0.501 0.04 0.07 34.2E−11 0.003 0.003 74.91.002 0.10 0.15 32.9E−11 0.008 0.007 74.9 4.002 0.48 0.60 29.7E−11 0.0300.030 75.0 6.996 0.91 1.01 24.0E−11 0.050 0.050 74.8 10.003 1.30 1.4332.5E−11 0.069 0.070 75.0 13.000 1.72 1.83 23.6E−11 0.087 0.087 75.015.002 2.01 2.11 29.2E−11 0.100 0.101 74.9 19.999 2.68 2.77 46.2E−110.127 0.129

Where the indefinite article “a” or “an” is used with respect to astatement or description of the presence of a feature, component or stepin a composition, apparatus or process of this invention, it is to beunderstood, unless the statement or description explicitly provides tothe contrary, that the use of such indefinite article does not limit thepresence of the feature, component or step in the composition, apparatusor process to one in number.

Where a apparatus or process of this invention is stated or described ascomprising, including, containing, having, being composed of or beingconstituted by certain features, components or steps, it is to beunderstood, unless the statement or description explicitly provides tothe contrary, that one or more features, components or steps in additionto those explicitly stated or described may be present in the apparatusor process. In an alternative embodiment, however, the apparatus orprocess of this invention may be stated or described as consistingessentially of certain features, components or steps, in whichembodiment features, components or steps that would materially alter theprinciple of operation or the distinguishing characteristics of thecomposition, apparatus or process are not present therein. In a furtheralternative embodiment, the apparatus or process of this invention maybe stated or described as consisting of certain features, components orsteps, in which embodiment features, components or steps other than asnamed are not present therein.

1. An apparatus for temperature adjustment comprising (a) a compressorthat increases the pressure of the vapor of at least one refrigerant,wherein the compressor comprises moving parts that are lubricated by atleast one ionic liquid; (b) a condenser that receives refrigerant vaporthat is passed out of the compressor, and condenses the vapor underpressure to a liquid; (c) a pressure reduction device that receivesliquid refrigerant that is passed out of the condenser, and reduces thepressure of the liquid to form a mixture of refrigerant in liquid andvapor form; (d) an evaporator that receives the mixture of liquid andvapor refrigerant that is passed out of the pressure reduction device,and evaporates the remaining liquid in the mixture to form refrigerantvapor; and (e) a conduit that returns to the compressor refrigerantvapor that is passed out of the evaporator.
 2. An apparatus according toclaim 1 wherein the condenser is located in proximity to an object,medium or space to be heated.
 3. An apparatus according to claim 1wherein the evaporator is located in proximity to an object, medium orspace to be cooled.
 4. An apparatus according to claim 1 wherein arefrigerant is selected from the group consisting of CHClF₂ (R-22); CHF₃(R-23); CH₂F₂ (R-32); CH₃F (R-41); CHF₂CF₃ (R-125); CH₂FCF₃ (R-134a);CHF₂OCHF₂ (E-134); CH₃CClF₂ (R-142b); CH₃CF₃ (R-143a); CH₃CHF₂ (R-152a);CH₃CH₂F (R-161); CH₃OCH₃ (E170); CF₃CF₂CF₃ (R-218); CF₃CHFCF₃ (R-227ea);CF₃CH₂CF₃ (R-236fa); CH₂FCF₂CHF₂ (R-245ca); CHF₂CH₂CF₃ (R-245fa);CH₃CH₂CH₃ (R-290); CH₃CH₂CH₂CH₃ (R-600); CH(CH₃)₂CH₃ (R-600a);CH₃CH₂CH₂CH₂CH₃ (R-601); (CH₃)₂CHCH₂CH₃ (R-601a); CH₃CH₂OCH₂CH₃ (R-610);NH₃; CO₂; and CH₃CH═CH₂; and combinations thereof; or a refrigerantblend selected from the group consisting R-404A; R-407A; R-407B; R-407C;R-407D; R-407E; R-410A; R-410B; R-413A; 417A; R-419A; R-420A; 80.6%R-134a and 19.4% R-142b (by weight); R-421A; R-421B; R-422A; R-422B;R-422C; R-422D; R423A; R-424A; R-425A; R-426A; R-427A; 2.0% R-32, 41.0%R-125, 50.0% R-143a and 7.0% R-134a (by weight); 10.0% R-32, 33.0%R-125, 36.0% R-143a and 21.0% R-134a (by weight); R-428A; and R-507A. 5.An apparatus according to claim 2, wherein a refrigerant is selectedfrom the group consisting of R-22, R-32, R-125, R-134a, R-404A, R-410A,R-413A, R-422A, R-422D, R-423A, R-426A, R-427A R-507A, and combinationsthereof.
 6. An apparatus according to claim 1 wherein a refrigerantcomprises at least one hydrofluorocarbon selected from the groupconsisting of trifluoromethane (HFC-23), difluoromethane (HFC-32),pentafluoroethane (HFC-125), 1,1,2,2-tetrafluoroethane (HFC-134),1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1-trifluoroethane (HFC-143a),1,1-difluoroethane (HFC-152a), fluoroethane (HFC-161), R-404A, R-407C,R-410A, and combinations thereof.
 7. An apparatus according to claim 4wherein a refrigerant comprises at least one hydrofluorocarbon selectedfrom the group consisting of pentafluoroethane (HFC-125),1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoroethane(HFC-134a), R-404aA, R-407C, R-410A, and combinations thereof.
 8. Anapparatus according to claim 1 wherein a refrigerant comprises at leastone fluoroolefin selected from the group consisting of: (i)fluoroolefins of the formula E- or Z-R¹CH═CHR², wherein R¹ and R² are,independently, C₁ to C₆ perfluoroalkyl groups, and wherein the totalnumber of carbons in the compound is at least 5; (ii) cyclicfluoroolefins of the formula cyclo-[CX═CY(CZW)_(n)-], wherein X, Y, Z,and W, independently, are H or F, and n is an integer from 2 to 5; and(iii) fluoroolefins selected from the group consisting of:2,3,3-trifluoro-1-propene (CHF₂CF═CH₂); 1,1,2-trifluoro-1-propene(CH₃CF═CF₂); 1,2,3-trifluoro-1-propene (CH₂FCF═CF₂);1,1,3-trifluoro-1-propene (CH₂FCH═CF₂); 1,3,3-trifluoro-1-propene(CHF₂CH═CHF); 1,1,1,2,3,4,4,4-octafluoro-2-butene (CF₃CF═CFCF₃);1,1,2,3,3,4,4,4-octafluoro-1-butene (CF₃CF₂CF═CF₂);1,1,1,2,4,4,4-heptafluoro-2-butene (CF₃CF═CHCF₃);1,2,3,3,4,4,4-heptafluoro-1-butene (CHF═CFCF₂CF₃);1,1,1,2,3,4,4-heptafluoro-2-butene (CHF₂CF═CFCF₃);1,3,3,3-tetrafluoro-2-(trifluoromethyl)-1-propene ((CF₃)₂C═CHF);1,1,3,3,4,4,4-heptafluoro-1-butene (CF₂═CHCF₂CF₃);1,1,2,3,4,4,4-heptafluoro-1-butene (CF₂═CFCHFCF₃);1,1,2,3,3,4,4-heptafluoro-1-butene (CF₂═CFCF₂CHF₂);2,3,3,4,4,4-hexafluoro-1-butene (CF₃CF₂CF═CH₂);1,3,3,4,4,4-hexafluoro-1-butene (CHF═CHCF₂CF₃);1,2,3,4,4,4-hexafluoro-1-butene (CHF═CFCHFCF₃);1,2,3,3,4,4-hexafluoro-1-butene (CHF═CFCF₂CHF₂);1,1,2,3,4,4-hexafluoro-2-butene (CHF₂CF═CFCHF₂);1,1,1,2,3,4-hexafluoro-2-butene (CH₂FCF═CFCF₃);1,1,1,2,4,4-hexafluoro-2-butene (CHF₂CH═CFCF₃);1,1,1,3,4,4-hexafluoro-2-butene (CF₃CH═CFCHF₂);1,1,2,3,3,4-hexafluoro-1-butene (CF₂═CFCF₂CH₂F);1,1,2,3,4,4-hexafluoro-1-butene (CF₂═CFCHFCHF₂);3,3,3-trifluoro-2-(trifluoromethyl)-1-propene (CH₂═C(CF₃)₂);1,1,1,2,4-pentafluoro-2-butene (CH₂FCH═CFCF₃);1,1,1,3,4-pentafluoro-2-butene (CF₃CH═CFCH₂F);3,3,4,4,4-pentafluoro-1-butene (CF₃CF₂CH═CH₂);1,1,1,4,4-pentafluoro-2-butene (CHF₂CH═CHCF₃);1,1,1,2,3-pentafluoro-2-butene (CH₃CF═CFCF₃);2,3,3,4,4-pentafluoro-1-butene (CH₂═CFCF₂CHF₂);1,1,2,4,4-pentafluoro-2-butene (CHF₂CF═CHCHF₂);1,1,2,3,3-pentafluoro-1-butene (CH₃CF₂CF═CF₂);1,1,2,3,4-pentafluoro-2-butene (CH₂FCF═CFCHF₂);1,1,3,3,3-pentafluoro-2-methyl-1-propene (CF₂═C(CF₃)(CH₃));2-(difluoromethyl)-3,3,3-trifluoro-1-propene (CH₂═C(CHF₂)(CF₃));2,3,4,4,4-pentafluoro-1-butene (CH₂═CFCHFCF₃);1,2,4,4,4-pentafluoro-1-butene (CHF═CFCH₂CF₃);1,3,4,4,4-pentafluoro-1-butene (CHF═CHCHFCF₃);1,3,3,4,4-pentafluoro-1-butene (CHF═CHCF₂CHF₂);1,2,3,4,4-pentafluoro-1-butene (CHF═CFCHFCHF₂);3,3,4,4-tetrafluoro-1-butene (CH₂═CHCF₂CHF₂);1,1-difluoro-2-(difluoromethyl)-1-propene (CF₂═C(CHF₂)(CH₃));1,3,3,3-tetrafluoro-2-methyl-1-propene (CHF═C(CF₃)(CH₃));3,3-difluoro-2-(difluoromethyl)-1-propene (CH₂═C(CHF₂)₂);1,1,1,2-tetrafluoro-2-butene (CF₃CF═CHCH₃); 1,1,1,3-tetrafluoro-2-butene(CH₃CF═CHCF₃); 1,1,1,2,3,4,4,5,5,5-decafluoro-2-pentene(CF₃CF═CFCF₂CF₃); 1,1,2,3,3,4,4,5,5,5-decafluoro-1-pentene(CF₂═CFCF₂CF₂CF₃); 1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-2-butene((CF₃)₂C═CHCF₃); 1,1,1,2,4,4,5,5,5-nonafluoro-2-pentene(CF₃CF═CHCF₂CF₃); 1,1,1,3,4,4,5,5,5-nonafluoro-2-pentene(CF₃CH═CFCF₂CF₃); 1,2,3,3,4,4,5,5,5-nonafluoro-1-pentene(CHF═CFCF₂CF₂CF₃); 1,1,3,3,4,4,5,5,5-nonafluoro-1-pentene(CF₂═CHCF₂CF₂CF₃); 1,1,2,3,3,4,4,5,5-nonafluoro-1-pentene(CF₂═CFCF₂CF₂CHF₂); 1,1,2,3,4,4,5,5,5-nonafluoro-2-pentene(CHF₂CF═CFCF₂CF₃); 1,1,1,2,3,4,4,5,5-nonafluoro-2-pentene(CF₃CF═CFCF₂CHF₂); 1,1,1,2,3,4,5,5,5-nonafluoro-2-pentene (CF₃CF═CFCHFCF₃); 1,2,3,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene(CHF═CFCF(CF₃)₂); 1,1,2,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene(CF₂═CFCH(CF₃)₂); 1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-2-butene(CF₃ CH═C(CF₃)₂); 1,1,3,4,4,4-hexafluoro-3-(trifluoromethyl)-1-butene(CF₂═CHCF(CF₃)₂); 2,3,3,4,4,5,5,5-octafluoro-1-pentene(CH₂═CFCF₂CF₂CF₃); 1,2,3,3,4,4,5,5-octafluoro-1-pentene(CHF═CFCF₂CF₂CHF₂); 3,3,4,4,4-pentafluoro-2-(trifluoromethyl)-1-butene(CH₂═C(CF₃)CF₂CF₃); 1,1,4,4,4-pentafluoro-3-(trifluoromethyl)-1-butene(CF₂═CHCH(CF₃)₂); 1,3,4,4,4-pentafluoro-3-(trifluoromethyl)-1-butene(CHF═CHCF(CF₃)₂); 1,1,4,4,4-pentafluoro-2-(trifluoromethyl)-1-butene(CF₂═C(CF₃)CH₂CF₃); 3,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene((CF₃)₂CFCH═CH₂); 3,3,4,4,5,5,5-heptafluoro-1-pentene (CF₃CF₂CF₂CH═CH₂);2,3,3,4,4,5,5-heptafluoro-1-pentene (CH₂═CFCF₂CF₂CHF₂);1,1,3,3,5,5,5-heptafluoro-1-butene (CF₂═CHCF₂CH₂CF₃);1,1,1,2,4,4,4-heptafluoro-3-methyl-2-butene (CF₃CF═C(CF₃)(CH₃));2,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene (CH₂═CFCH(CF₃)₂);1,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene (CHF═CHCH(CF₃)₂);1,1,1,4-tetrafluoro-2-(trifluoromethyl)-2-butene (CH₂FCH═C(CF₃)₂);1,1,1,3-tetrafluoro-2-(trifluoromethyl)-2-butene (CH₃CF═C(CF₃)₂);1,1,1-trifluoro-2-(trifluoromethyl)-2-butene ((CF₃)₂C═CHCH₃);3,4,4,5,5,5-hexafluoro-2-pentene (CF₃CF₂CF═CHCH₃);1,1,1,4,4,4-hexafluoro-2-methyl-2-butene (CF₃C(CH₃)═CHCF₃);3,3,4,5,5,5-hexafluoro-1-pentene (CH₂═CHCF₂CHFCF₃);4,4,4-trifluoro-3-(trifluoromethyl)-1-butene (CH₂═C(CF₃)CH₂CF₃);1,1,2,3,3,4,4,5,5,6,6,6-dodecafluoro-1-hexene (CF₃(CF₂)₃CF═CF₂);1,1,1,2,2,3,4,5,5,6,6,6-dodecafluoro-3-hexene (CF₃CF₂CF═CFCF₂CF₃);1,1,1,4,4,4-hexafluoro-2,3-bis(trifluoromethyl)-2-butene((CF₃)₂C═C(CF₃)₂);1,1,1,2,3,4,5,5,5-nonafluoro-4-(trifluoromethyl)-2-pentene((CF₃)₂CFCF═CFCF₃);1,1,1,4,4,5,5,5-octafluoro-2-(trifluoromethyl)-2-pentene((CF₃)₂C═CHC₂F₅);1,1,1,3,4,5,5,5-octafluoro-4-(trifluoromethyl)-2-pentene((CF₃)₂CFCF═CHCF₃); 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene(CF₃CF₂CF₂CF₂CH═CH₂); 4,4,4-trifluoro-3,3-bis(trifluoromethyl)-1-butene(CH₂═CHC(CF₃)₃);1,1,1,4,4,4-hexafluoro-2-(trifluoromethyl)-3-methyl-2-butene((CF₃)₂C═C(CH₃)(CF₃));2,3,3,5,5,5-hexafluoro-4-(trifluoromethyl)-1-pentene(CH₂═CFCF₂CH(CF₃)₂); 1,1,1,2,4,4,5,5,5-nonafluoro-3-methyl-2-pentene(CF₃CF═C(CH₃)CF₂CF₃);1,1,1,5,5,5-hexafluoro-4-(trifluoromethyl)-2-pentene (CF₃CH═CHCH(CF₃)₂);3,4,4,5,5,6,6,6-octafluoro-2-hexene (CF₃CF₂CF₂CF═CHCH₃);3,3,4,4,5,5,6,6-octafluoro 1-hexene (CH₂═CHCF₂CF₂CF₂CHF₂);1,1,1,4,4-pentafluoro-2-(trifluoromethyl)-2-pentene ((CF₃)₂C═CHCF₂CH₃);4,4,5,5,5-pentafluoro-2-(trifluoromethyl)-1-pentene (CH₂═C(CF₃)CH₂C₂F₅);3,3,4,4,5,5,5-heptafluoro-2-methyl-1-pentene (CF₃CF₂CF₂C(CH₃)═CH₂);4,4,5,5,6,6,6-heptafluoro-2-hexene (CF₃CF₂CF₂CH═CHCH₃);4,4,5,5,6,6,6-heptafluoro-1-hexene (CH₂═CHCH₂CF₂C₂F₅);1,1,1,2,2,3,4-heptafluoro-3-hexene (CF₃CF₂CF═CFC₂H₅);4,5,5,5-tetrafluoro-4-(trifluoromethyl)-1-pentene (CH₂═CHCH₂CF(CF₃)₂);1,1,1,2,5,5,5-heptafluoro-4-methyl-2-pentene (CF₃CF═CHCH(CF₃)(CH₃));1,1,1,3-tetrafluoro-2-(trifluoromethyl)-2-pentene ((CF₃)₂C═CFC₂H₅); 1,1, 1, 2, 3,4,4,5,5,6,6,7,7,7-tetradecafluoro-2-heptene(CF₃CF═CFCF₂CF₂C₂F₅);1,1,1,2,2,3,4,5,5,6,6,7,7,7-tetradecafluoro-3-heptene(CF₃CF₂CF═CFCF₂C₂F₅); 1,1,1,3,4,4,5,5,6,6,7,7,7-tridecafluoro-2-heptene(CF₃CH═CFCF₂CF₂C₂F₅); 1,1,1,2,4,4,5,5,6,6,7,7,7-tridecafluoro-2-heptene(CF₃CF═CHCF₂CF₂C₂F₅); 1,1,1,2,2,4,5,5,6,6,7,7,7-tridecafluoro-3-heptene(CF₃CF₂CH═CFCF₂C₂F₅); 1,1,1,2,2,3,5,5,6,6,7,7,7-tridecafluoro-3-heptene(CF₃CF₂CF═CHCF₂C₂F₅); CF₂═CFOCF₂CF₃ (PEVE) and CF₂═CFOCF₃ (PMVE).
 9. Anapparatus according to claim 1 wherein a refrigerant comprises (a)pentafluoroethane (R-125), 1,1,1,2-tetrafluoroethane (R-134a), and atleast two hydrocarbons each having eight or fewer carbon atoms, or (b)pentafluoroethane (R-125), 1,1,1,2-tetrafluoroethane (R-134a), n-butane(R-600) and n-pentane (R-601).
 10. An apparatus according to claim 1wherein an ionic liquid comprises a cation selected from the groupconsisting of the following eleven cations:

wherein R¹, R², R³, R⁴, K⁵ and R⁶ are independently selected from thegroup consisting of: (i) H (ii) halogen (iii) —CH₃, —C₂H₅, or C₃ to C₂₅straight-chain, branched or cyclic alkane or alkene, optionallysubstituted with at least one member selected from the group consistingof Cl, Br, F, I, OH, NH₂ and SH; (iv) —CH₃, —C₂H₅, or C₃ to C₂₅straight-chain, branched or cyclic alkane or alkene comprising one tothree heteroatoms selected from the group consisting of O, N, Si and S,and optionally substituted with at least one member selected from thegroup consisting of Cl, Br, F, I, OH, NH₂ and SH; (v) C₆ to C₂₀unsubstituted aryl, or C₃ to C₂₅ unsubstituted heteroaryl having one tothree heteroatoms independently selected from the group consisting of O,N, Si and S; and (vi) C₆ to C₂₅ substituted aryl, or C₃ to C₂₅substituted heteroaryl having one to three heteroatoms independentlyselected from the group consisting of O, N, Si and S; and wherein saidsubstituted aryl or substituted heteroaryl has one to three substituentsindependently selected from the group consisting of: (1) —CH₃, —C₂H₅, orC₃ to C₂₅ straight-chain, branched or cyclic alkane or alkene,optionally substituted with at least one member selected from the groupconsisting of Cl, Br, F I, OH, NH₂ and SH, (2) OH, (3) NH₂, and (4) SH;R⁷, R⁸, R⁹, and R¹⁰ are independently selected from the group consistingof: (vii) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or cyclicalkane or alkene, optionally substituted with at least one memberselected from the group consisting of Cl, Br, F, I, OH, NH₂ and SH;(viii) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched or cyclicalkane or alkene comprising one to three heteroatoms selected from thegroup consisting of O, N, Si and S, and optionally substituted with atleast one member selected from the group consisting of Cl, Br, F, I, OH,NH₂ and SH; (ix) C₆ to C₂₅ unsubstituted aryl, or C₃ to C₂₅unsubstituted heteroaryl having one to three heteroatoms independentlyselected from the group consisting of O, N, Si and S; and (x) C₆ to C₂₅substituted aryl, or C₃ to C₂₅ substituted heteroaryl having one tothree heteroatoms independently selected from the group consisting of O,N, Si and S; and wherein said substituted aryl or substituted heteroarylhas one to three substituents independently selected from the groupconsisting of: (1) —CH₃, —C₂H₅, or C₃ to C₂₅ straight-chain, branched orcyclic alkane or alkene, optionally substituted with at least one memberselected from the group consisting of Cl, Br, F, I, OH, NH₂ and SH, (2)OH, (3) NH₂, and (4) SH; and wherein optionally at least two of R¹, R²,R³, R⁴⁵, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰ can together form a cyclic orbicyclic alkanyl or alkenyl group.
 11. An apparatus according to claim10 wherein at least one of R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰comprises F⁻.
 12. An apparatus according to claim 1 wherein an ionicliquid comprises an anion selected from the group consisting of[CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻,[NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO₄]³⁻, [HPO₄]²⁻[H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻,Cl⁻, Br⁻, I⁻, SCN⁻, and any fluorinated anion.
 13. An apparatusaccording to claim 1 wherein an ionic liquid comprises an anion selectedfrom the group consisting of [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻,[HCF₂CF₂SO₃]⁻, [CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻,[(CF₃CF₂SO₂)₂N]⁻, [(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻,[CF₃CF₂OCFHCF₂SO₃]⁻, [CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻,[CF₂₁CF₂OCF₂CF₂SO₃]⁻, [CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N]⁻,[(CF₃CFHCF₂SO₂)₂N]⁻, and F⁻.
 14. An apparatus according to claim 1wherein an ionic liquid comprises a cation selected from the groupconsisting of pyridinium, pyridazinium, pyrimidinium, pyrazinium,imidazolium, pyrazolium, thiazolium, oxazolium, triazolium, phosphonium,or ammonium ions; and an anion selected from the group consisting of[CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻,[NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO_(4]3−), [HPO₄]²⁻[H₂PO₄]⁻, [HSO₃]⁻,[CuCl₂]⁻, Cl⁻, Br⁻, I⁻, SCN⁻, [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻,[HCF₂CF₂SO₃]⁻, [CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻,[(CF₃CF₂SO₂)₂N]⁻, [(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻,[CF₃CF₂OCFHCF₂SO₃]⁻, [CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻,[CF₂₁CF₂OCF₂CF₂SO₃]⁻, [CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N]⁻, and[(CF₃CFHCF₂SO₂)₂N]⁻.
 15. An apparatus according to claim 18 wherein anionic liquid comprises a cation selected from the group consisting of1-butyl-3-methylimidazolium, 1,2-dimethyl-3-propylimidazolium,1-octyl-3-methylimidazolium, 1,3-dioctylimidazolium,1-ethyl-3-methylimidazolium, 1-dodecyl-3-methylimidazolium,1-heptyl-3-methylimidazolium, 3-methyl-1-propylpyridinium,1-butyl-3-methylpyridinium, tetradecyl(trihexyl)phosphonium, ortributyl(tetradecyl)phosphonium ions; and an anion selected from thegroup consisting of [CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻,[AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻, [NO₂]⁻, [NO₃]⁻, [SO₄]²⁻, [PO_(4]3−),[HPO₄]²⁻[H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻, Cl⁻, Br⁻, I⁻, SCN⁻, [BF₄]⁻, [PF₆]⁻,[SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻, [CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻,[(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻, [(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻,[CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻, [CF₃CFHOCF₂CF₂SO₃]⁻,[CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂1CF₂OCF₂CF₂SO₃]⁻, [CF₃CF₂OCF₂CF₂SO₃]⁻,[(CF₂HCF₂SO₂)₂N]⁻, and [(CF₃CFHCF₂SO₂)₂N]⁻.
 16. An apparatus accordingto claim 1 wherein a refrigerant is selected from the group consistingof CHClF₂ (R-22), CHF₃ (R-23), CH₂F₂ (R-32), CH₃F (R-41), CHF₂CF₃(R-125), CH₂FCF₃ (R-134a), CHF₂OCHF₂ (E-134), CH₃CClF₂ (R-142b), CH₃CF₃(R-143a), CH₃CHF₂ (R-152a), CH₃CH₂F (R-161), CH₃OCH₃ (E170), CF₃CF₂CF₃(R-218), CF₃CHFCF₃ (R-227ea), CF₃CH₂CF₃ (R-236fa), CH₂FCF₂CHF₂(R-245ca), CHF₂CH₂CF₃ (R-245fa), CH₃CH₂CH₃ (R-290), CH₃CH₂CH₂CH₃(R-600), CH(CH₃)₂CH₃ (R-600a), CH₃CH₂CH₂CH₂CH₃ (R-601), (CH₃)₂CHCH₂CH₃(R-601a), CH₃CH₂OCH₂CH₃ (R-610), NH₃, CO₂, CH₃CH═CH₂, and combinationsthereof; and an ionic liquid comprises a cation selected from the groupconsisting of pyridinium, pyridazinium, pyrimidinium, pyrazinium,imidazolium, pyrazolium, thiazolium, oxazolium, triazolium, phosphonium,or ammonium ions; and an anion selected from the group consisting of[CH₃CO₂]⁻, [HSO₄]⁻, [CH₃OSO₃]⁻, [C₂H₅OSO₃]⁻, [AlCl₄]⁻, [CO₃]²⁻, [HCO₃]⁻,[NO₂]⁻, [NO₃]⁻, [SO₄]², [PO₄]³⁻, [HPO₄]²⁻, [H₂PO₄]⁻, [HSO₃]⁻, [CuCl₂]⁻,Cl⁻, Br⁻, I⁻, SCN⁻, [BF₄]⁻, [PF₆]⁻, [SbF₆]⁻, [CF₃SO₃]⁻, [HCF₂CF₂SO₃]⁻,[CF₃HFCCF₂SO₃]⁻, [HCClFCF₂SO₃]⁻, [(CF₃SO₂)₂N]⁻, [(CF₃CF₂SO₂)₂N]⁻,[(CF₃SO₂)₃C]⁻, [CF₃CO₂]⁻, [CF₃OCFHCF₂SO₃]⁻, [CF₃CF₂OCFHCF₂SO₃]⁻,[CF₃CFHOCF₂CF₂SO₃]⁻, [CF₂HCF₂OCF₂CF₂SO₃]⁻, [CF₂ICF₂OCF₂CF₂SO₃]⁻,[CF₃CF₂OCF₂CF₂SO₃]⁻, [(CF₂HCF₂SO₂)₂N], and [(CF₃CFHCF₂SO₂)₂N]⁻.
 17. Anapparatus according to claim 1 that is fabricated as a refrigerator, afreezer, an ice machine, an air conditioner, an industrial coolingsystem, heater or heat pump.
 18. An apparatus for temperature adjustmentcomprising (a) a compressor that increases the pressure of the vapor ofat least one refrigerant; (b) a condenser that receives refrigerantvapor that is passed out of the compressor, and condenses the vaporunder pressure to a liquid; (c) a pressure reduction device thatreceives liquid refrigerant that is passed out of the condenser, andreduces the pressure of the liquid to form a mixture of refrigerant inliquid and vapor form; (d) an evaporator that receives the mixture ofliquid and vapor refrigerant that is passed out of the pressurereduction device, and evaporates the remaining liquid in the mixture toform refrigerant vapor; and (e) a conduit that returns to the compressorrefrigerant vapor that is passed out of the evaporator; wherein arefrigerant is admixed with at least one ionic liquid.
 19. A process foradjusting the temperature of an object, medium or a space comprising (a)providing a mechanical device having moving parts to increase thepressure of the vapor of at least one refrigerant, and providing atleast one ionic liquid to lubricate the moving parts of the device; (b)condensing the refrigerant vapor under pressure to a liquid; (c)reducing the pressure of the liquid refrigerant to form a mixture ofrefrigerant in liquid and vapor form; (d) evaporating the liquidrefrigerant to form refrigerant vapor; and (e) repeating step (a) toincrease the pressure of the refrigerant vapor formed in steps (c) and(d).
 20. A process for adjusting the temperature of an object, medium ora space comprising (a) increasing the pressure of the vapor of at leastone refrigerant; (b) condensing the refrigerant vapor under pressure toa liquid; (c) reducing the pressure of the liquid refrigerant to form amixture of refrigerant in liquid and vapor form; (d) evaporating theliquid refrigerant to form refrigerant vapor; (e) separating from therefrigerant vapor any ionic liquid present therein; and (f) repeatingstep (a) to increase the pressure of the refrigerant vapor formed insteps (c) and (d).